[This document is no longer viewed as guidance for current medical practice.]
Acute Lower Back Problems in Adults
Clinical Practice Guideline 14AHCPR Publication No. 95-0642: December 1994
Thanks to the National Guideline Clearinghouse
Inside Front Cover
The
Agency for Health Care Policy and Research (AHCPR) was established in December
1989 under Public Law 101-239 (Omnibus Budget Reconciliation Act of 1989) to
enhance the quality, appropriateness, and effectiveness of health care
services and access to these services. AHCPR carries out its mission by
conducting and supporting general health services research, including medical
effectiveness research, facilitating development of clinical practice
guidelines, and disseminating research findings and guidelines to health care
providers, policymakers, and the public.
The legislation also
established within AHCPR the Office of the Forum for Quality and Effectiveness
in Health Care (the Forum). The Forum has primary responsibility for
facilitating the development, periodic review, and updating of clinical
practice guidelines. The guidelines will assist practitioners in the
prevention, diagnosis, treatment, and management of clinical conditions.
Other AHCPR components include the following. The Center for Medical
Effectiveness Research has principal responsibility for patient outcomes
research and studies of variations in clinical practice. The Center for General
Health Services Extramural Research supports research on primary care, the
cost and financing of health care, and access to care for underserved and
rural populations. The Center for General Health Services Intramural Research
uses large data sets for policy research on national health care expenditures
and utilization, hospital studies, and long-term care. The Center for Research
Dissemination and Liaison produces and disseminates findings from
AHCPR-supported research, including guidelines, and conducts research on
dissemination methods. The Office of Health Technology Assessment responds to
requests from Federal health programs for assessment of health care
technologies. The Office of Science and Data Development develops specialized
databases and enhances techniques for using existing databases for patient
outcomes research.
Guidelines are available in formats suitable for
health care practitioners, the scientific community, educators, and
consumers. AHCPR invites comments and suggestions from users for consideration
in development and updating of future guidelines. Please send written comments
to Director, Office of the Forum for Quality and Effectiveness in Health Care,
AHCPR, Willco Building, Suite 310, 6000 Executive Boulevard, Rockville, MD
20852.
Availability of Guidelines
For each
clinical practice guideline developed under the sponsorship of the Agency for
Health Care Policy and Research (AHCPR), several versions are produced to meet
different needs.
The Clinical Practice Guideline presents
recommendations for health care providers with brief supporting information,
tables and figures, and pertinent references.
The Quick Reference
Guide for Clinicians is a distilled version of the Clinical Practice
Guideline, with summary points for ready reference on a day-to-day basis.
The Consumer Version, available in English and Spanish, is an
information booklet for the general public to increase patient knowledge and
involvement in health care decisionmaking.
To order single copies of
guideline products or to obtain further information on their availability,
call the AHCPR Publications Clearinghouse toll-free at 800-358-9295 or write
to: AHCPR Publications Clearinghouse, P.O. Box 8547, Silver Spring, MD 20907.
Single copies of the Clinical Practice Guideline are available
for sale from the Government Printing Office, Superintendent of Documents,
Washington, DC 20402, with a 25-percent discount given for bulk orders of 100
copies of more. The Quick Reference Guide for Clinicians and the Consumer Version in English are also available for sale in bulk quantities
only. Call (202) 512-1800 for price and ordering information.
The Guideline Technical Report contains complete supporting materials for the
Clinical Practice Guideline, including background information,
methodology, literature review, scientific evidence tables, recommendations
for research, and a comprehensive bibliography. It is available from the
National Technical Information Service, 5285 Port Royal Road, Springfield, VA
22161. Call (703) 487-4650 for price and ordering information.
The full
text of guideline documents for online retrieval may be accessed through a
free, electronic service from the National Library of Medicine called HSTAT
(Health Services/Technology Assessment Text). Guideline information is also
available through some of the computer-based information systems of the
National Technical Information Service, professional associations, nonprofit
organizations, and commercial enterprises.
A fact sheet describing
Online Access for Clinical Practice Guidelines (AHCPR Publication No. 94-0075)
and copies of the Quick Reference Guide for Clinicians and the Consumer Version of each guideline are available through AHCPR's
InstantFAX, a fax-on-demand service that operates 24 hours a day, 7 days a
week. AHCPR's InstantFAX is accessible to anyone using a facsimile machine
equipped with a touchtone telephone handset: Dial (301) 594-2800, push "1",
and then press the facsimile machine's start button for instructions and a
list of currently available publications.
Acute Lower Back Problems in Adults
Guideline Development and Use
Guidelines are systematically developed statements
to assist practitioner and patient decisions about appropriate health care.
This guideline was developed by an independent multidisciplinary panel of
private-sector clinicians and other experts convened by the Agency for Health
Care Policy and Research (AHCPR). The panel employed explicit, science-based
methods and expert clinical judgment to develop specific statements on acute
low back problems in adults.
Extensive literature searches were
conducted and critical reviews and syntheses were used to evaluate empirical
evidence and significant outcomes. Peer review and field review were undertaken
to evaluate the validity, reliability, and utility of the guideline in
clinical practice. The panel's recommendations are primarily based on the
published scientific literature. When the scientific literature was incomplete
or inconsistent in a particular area, the recommendations reflect the
professional judgment of panel members and consultants.
The guideline
reflects the state of knowledge, current at the time of publication. Given the
inevitable changes in the state of scientific information and technology,
periodic review, updating, and revision will be done.
We believe that
the AHCPR-assisted clinical guidelines will make positive contributions to the
quality of care in the United States. We encourage practitioners and patients
to use the information provided in this Clinical Practice Guideline.
The recommendations may not be appropriate for use in all circumstances.
Decisions to adopt any particular recommendation must be made by the
practitioner in light of available resources and circumstances presented by
individual patients.
- Clifton R. Gaus, ScD
- Administrator
- Agency for Health Care Policy and Research
Publication of this guideline does not necessarily represent an endorsement by the U.S. Department of Health and Human Services
Abstract
Findings and recommendations on the assessment and treatment of adults with acute low back problems-activity limitations due to symptoms in the low back and/or back-related leg symptoms of less than 3 months' duration-are presented in this clinical practice guideline. The following are the principal conclusions of this guideline:
The initial assessment of patients with acute low back problems focuses on the detection of "red flags" (indicators of potentially serious spinal pathology or other nonspinal pathology).
In the absence of red flags, imaging studies and further testing of patients are not usually helpful during the first 4 weeks of low back symptoms.
Relief of discomfort can be accomplished most safely with nonprescription medication and/or spinal manipulation.
While some activity modification may be necessary during the acute phase, bed rest >4 days is not helpful and may further debilitate the patient.
Low-stress aerobic activities can be safely started in the first 2 weeks of symptoms to help avoid debilitation; exercises to condition trunk muscles are commonly delayed at least 2 weeks.
Patients recovering from acute low back problems are encouraged to return to work or their normal daily activities as soon as possible.
If low back symptoms persist, further evaluation may be indicated.
Patients with sciatica may recover more slowly, but further evaluation can also be safely delayed.
Within the first 3 months of low back symptoms, only patients with evidence of serious spinal pathology or severe, debilitating symptoms of sciatica, and physiologic evidence of specific nerve root compromise corroborated on imaging studies can be expected to benefit from surgery.
With or without surgery, 80 percent of patients with sciatica recover eventually.
Nonphysical factors (such as psychological or socioeconomic problems) may be addressed in the context of discussing reasonable expectations for recovery.
This document is in the public domain and may be used and reprinted
without special permission.
AHCPR will appreciate citation of the source, and the suggested format is provided below:
- Bigos S, Bowyer O, Braen G, et
al. Acute Low Back Problems in Adults. Clinical Practice Guideline No. 14.
AHCPR Publication No. 95-0642. Rockville, MD: Agency for Health Care Policy and Research, Public Health Service, U.S. Department of Health and Human Services. December 1994.
Panel Members
Executive Summary
Acute low back
problems, the subject of this Clinical Practice Guideline, are
experienced by almost everyone at some time in their adult lives. Back problems
rank high among the reasons for physician office visits and are costly in
terms of medical treatment, time lost from work, and nonmonetary costs such as
diminished ability to perform or enjoy usual activities. For persons under age
45, low back problems are the most frequent cause of disability.
The initial assessment of a patient with
activity intolerance due to low back symptoms consists of a focused medical
history and physical examination. The primary purpose is to seek medical
history responses or physical examination findings that suggest a serious
underlying spinal condition such as fracture, tumor, infection, or cauda
equina syndrome. These responses or findings are referred to as "red flags."
The history and physical examination should also assess for nonspinal
conditions (vascular, abdominal, urinary, or pelvic pathology) causing
referred low back symptoms. In the
absence of the red flags described above, most patients with activity
intolerance due to an acute episode of low back symptoms can be treated
similarly during the first month. The goals are to provide patients with
accurate information about low back problems, assist with symptom relief, and
make appropriate activity recommendations. The panel
recommended that clinicians consider a diagnostic reevaluation that may
include special studies if the patient continues to be limited by back
symptoms for more than 1 month without improvement. This reevaluation begins
with a review and update of the history and physical exam to look again for
red flags or evidence of nonspinal conditions causing back symptoms. If none
of these is found, an appropriate evaluation can be initiated for either
patients with sciatica or those with nonspecific low back symptoms.
The
Agency for Health Care Policy and Research (AHCPR) convened a 23-member,
multidisciplinary, private-sector panel to develop a guideline for the
evaluation and treatment of acute low back problems in adults. The panel
included physicians, nurses, chiropractors, experts in spine research,
physical therapists, a psychologist, an occupational therapist, and a consumer
representative. The panel defined back problems as activity intolerance due to
back-related symptoms and acute as limitations of less than 3 months'
duration. Back symptoms include pain, primarily in the back, as well as
back-related leg pain (sciatica). The panel agreed that the guideline should
provide primary care clinicians with information on the detection of serious
spinal pathology (such as tumor or infection, spinal fracture or cauda equina
syndrome) as well as nonspinal pathology that could be causing limitations due
to low back symptoms, but that treatment of these conditions is outside the
scope of the guideline.
Furthermore, the panel agreed that the
assessment and treatment of patients younger than 18 years or those with
chronic low back problems (back-related limitations lasting longer than 3
months) may be quite different than for adults with acute problems. For this
reason, the panel decided that back problems in children as well as chronic
low back problems are also outside the scope of the guideline.
The
panel's overall intent was to change the paradigm of focusing care exclusively
on the pain of low back problems to one of helping patients improve their
activity tolerance. Findings and recommendation statements are based on an
exhaustive and systematic review and analysis of the scientific literature as
well as information gathered from the clinical experience of the expert panel,
public testimony, peer review, and pretesting in outpatient settings. This
guideline is divided into an introduction and three chapters to correlate with
the clinical approach: (1) Initial Assessment Methods; (2) Clinical Care
Methods; and (3) Special Studies and Diagnostic Considerations. Initial Assessment Methods
Once the clinician has ruled out red flags
and nonspinal pathology, the symptoms can be categorized as either sciatica or
nonspecific back pain. In the absence of red flags, neither routine nor special
testing is required in the first month of symptoms for either category. Most
of these patients will recover spontaneously from their activity limitations
within 1 month. Clinical Care Methods
Once the history and
physical examination are complete, the patient can be assured that there is no
hint of a dangerous medical condition causing the back problem and that a
rapid recovery is expected. Symptom control methods focus initially on
providing the patient with a comfort level adequate to keep the patient as
active as possible while awaiting spontaneous recovery. Later in treatment,
symptom control is considered an adjunct in helping the patient overcome a
specific activity intolerance. The primary methods of symptom control are oral
pharmaceuticals and physical methods.
Among the oral medications
available to control the discomfort of acute low back problems, the panel
recommends acetaminophen as reasonably safe and acceptable. Nonsteroidal
anti-inflammatory drugs (NSAIDs), including aspirin, are also acceptable
despite the potential for side effects, most frequently gastrointestinal
irritation. Muscle relaxants, including benzodiazepines, have been found no
more effective than NSAIDs in treating patients with acute low back problems,
and potential side effects of these drugs include drowsiness in up to 30
percent of patients. The panel recommended that opioids be avoided if possible
because of significant risks of debilitation, drowsiness, decreased reaction
time, clouded judgment, and potential misuse. If chosen, they should be used
only for a short time. The panel also recommended against the use of oral
steroids, colchicine, or antidepressant medications for acute low back
problems.
The panel found manipulation to be a recommendable method of
symptom control. Manipulation seems helpful for patients with acute low back
problems without radiculopathy when used within the first month of symptoms.
If no symptomatic and functional improvement has been noted after 1 month of
manipulative therapy, this treatment should be stopped and the patient
reevaluated. The panel found no evidence of benefit from the application of
physical agents and modalities such as ice, heat, massage, traction,
ultrasound, cutaneous laser treatment, transcutaneous electrical nerve
stimulation (TENS), and biofeedback techniques. Self-application of heat or
cold may be taught to patients who choose such options to provide temporary
relief of symptoms. Evidence does not support the use of trigger point,
ligamentous and facet joint injections, needle acupuncture, or dry needling as
treatment for acute low back problems.
The panel found that prolonged
bed rest (for more than 4 days) may lead to debilitation and is not
appropriate in the treatment of acute low back problems. A gradual return to
normal activities is advisable, although bed rest for 2 to 4 days may be an
option for patients with severe initial symptoms of sciatica. The patient
whose symptoms are aggravated by lifting or prolonged sitting may require
specific advice and exploration of alternatives. For most patients, aerobic
activities that minimally stress the back (such as walking, biking, or
swimming) can be started during the first 2 weeks of acute low back problems.
After this, conditioning exercises for trunk muscles (in particular back
extensors) may be helpful, especially if the patient's acute low back problems
persist, although such exercises may initially aggravate symptoms. Special Studies and Diagnostic Considerations
For
patients limited by sciatica for more than 4 weeks without clear evidence on
physical examination of nerve root compromise, electromyography
(EMG) and H-reflex tests of the lower limb may provide evidence of suspected
neurologic dysfunction. Sensory evoked potentials (SEPs) may be a useful
adjunct for assessment of suspected spinal stenosis or spinal cord
myelopathy. For patients limited by sciatica for more than 4 weeks with
physiologic evidence of neurologic dysfunction, MRI or CT is an appropriate
consideration to provide anatomic definition of suspected herniated disc
before surgery. Anatomic abnormalities of the lumbar spine (such as
degenerative changes or abnormal discs) can be confusing since they increase
in frequency as patients age and are often noted on imaging tests in subjects
with no symptoms of low back problems. Abnormalities on imaging should
corroborate evidence from physical examination or physiologic testing. A
referral for surgical consultation is reasonable for patients with sciatic
symptoms who have (1) activity limitations for more than 1 month without
improvement, (2) clear clinical or electrophysiological evidence of nerve root
compromise, and (3) corroborative findings on imaging studies. Earlier
emergency consultation is reserved for patients with findings of bowel and/or
bladder dysfunction or progressive and/or severe neurologic impairment. Most
patients with symptoms persisting beyond 4 weeks will not be surgical
candidates since the majority will have nonspecific acute low back symptoms
without evidence of a serious underlying condition.
Following
diagnostic or surgical procedures, treatment for those patients who have not
recovered focuses on graduated physical conditioning to gain tolerance for
activities required at home and/or the workplace. To help patients who have
extreme difficulty overcoming their personal activity intolerance, clinicians
are encouraged to address any nonphysical factors (such as unrealistic
expectations by patient or employer or other psychosocial problems) that can
potentially be influenced in a positive manner. The goal is to help the
patient recover normal activity tolerance and avoid the development of a
chronic low back disability.
1. Overview
There are four principal reasons acute low back problems were selected as a
subject for guideline development. One reason is their prevalence. Most people
report low back problems at some time in their lives, and national statistics
indicate a general yearly prevalence in the U.S. population of 15-20 percent.
[1] Among
working-age people surveyed, 50 percent admit to back symptoms each year.
[2],
[3] Back
symptoms, in fact, are the most common cause of disability for persons under
age 45. [4]
At any given time, about 1 percent of the U.S. population is chronically
disabled because of back problems, and another 1 percent temporarily disabled.
[1]
This Clinical Practice Guideline is
intended to provide primary care clinicians with information and recommended
strategies for the assessment and treatment of acute low back problems in
adults. To develop this guideline, AHCPR convened a private-sector,
multidisciplinary panel of clinicians, researchers, and a consumer
representative to evaluate the scientific evidence in the medical literature,
draw conclusions, and make recommendations. The panel agreed that this guideline on acute low back problems should
be anchored to published scientific evidence, and that such evidence should
take priority over panel opinion in making guideline recommendations. In
looking at a proposed assessment or treatment method, the panel considered:
(1) efficacy, (2) potential harms, and (3) costs. The panel found that, to date, studies of interventions aimed at preventing
low back problems or their risk factors present conflicting findings and
explain only a small portion of back complaints. Few of these prevention
studies have been well designed, and most have been conducted in workplace
settings focusing on injury claims or have used interventions that could not
easily be carried out by primary care providers. When information from these
studies was applicable to primary care, however, it was included under
specific areas of assessment or treatment in the guidelines. Chapter 2 of this guideline focuses on the initial assessment of the
patient with activity limitations due to acute low back symptoms, and
Chapter 3
addresses initial treatment methods for these patients. The assessment and
treatment methods considered in these chapters can typically be managed by the
primary care clinician. Up to 90 percent of patients with acute low back
problems recover within 1 month from activity limitations due to symptoms.
[6],
[14],
[15]
Chapter 4 addresses diagnostic and treatment considerations for the small percentage
of patients who still have substantial symptoms or limitations after 1 month.
Many of these diagnostic and therapeutic methods can be managed by the primary
care clinician; others will require consultation with a specialist. Potentially serious spinal
condition: spinal tumor, infection, fracture, or cauda equina syndrome
suggested by findings from medical history or physical examination ("red
flags"). Sciatica: back-related lower limb symptoms suggesting
nerve root compromise. Nonspecific back symptoms: symptoms
occurring primarily in the back that suggest neither nerve root compromise nor
a serious underlying condition.
In the panel's opinion,
clinicians would have enough information to make appropriate decisions about
initial assessment and treatment, as well as some hints about prognosis, after
correctly classifying patients with low back problems into one of the above
three categories. The panel used this classification scheme in making guideline
recommendations about assessment and treatment methods. The
general theory and principles underlying development of clinical practice
guidelines are presented in an Institute of Medicine report;
[17] other
reports published by AHCPR provide specific information on the clinical
guideline development process.
[18] These
materials provided a starting point for developing the Clinical Practice
Guideline on low back problems. AHCPR provided the general parameters for
guideline development. The panel, aided by the methodologists and consultants,
then independently determined the specific methodology for the project,
directed the literature review, and developed the guideline findings and
recommendations. AHCPR initiated formation of the panel and appointed its
chairperson and members. Important considerations in the choice of panel
members were: (1) demonstrated knowledge about low back problems, (2)
representation of major clinical disciplines involved in back care, and (3)
geographic diversity. Nominations were solicited through a Federal Register announcement and from professional and consumer organizations and persons
interested in the care of patients with low back problems. An
open forum was held early in the guideline development process to give
interested individuals, organizations, and agencies the opportunity to present
written or verbal testimony. Later in the process, drafts of the guideline
were sent out for peer and pilot review. AHCPR selected peer and pilot
reviewers from those who had expressed interest in the guideline, participated
in the open forum, or were nominated by professional organizations or panel
members. The panel initiated a
comprehensive literature search of topics deemed applicable to low back
problems. The Quebec Task Force on Spinal Disorders had previously published an
evidence-based guideline on low back problems, based upon an exhaustive
literature search through 1984.
[19] The
bibliography from their report was the starting point in the literature search
for this AHCPR guideline. In evaluating efficacy
of assessment and treatment methods, the panel decided to focus on how each
method affected clinical outcomes important to patients and society. Examples
of such outcomes are symptoms, level of physical functioning, patient
satisfaction, and morbidity and mortality (as complications of the assessment
or treatment method). The panel dealt with costs, another outcome of interest
to patients and society, as a separate issue. Cost was not considered when
evaluating efficacy. Since back problems are rarely life-threatening, the panel
paid special attention to potential harms (side effects or complications) of
assessment and treatment methods. Controlled trials evaluating treatment and
assessment methods, however, seldom included enough subjects to detect rare
but potentially serious complications. This information was found only in large
case series or case reports. On the other hand, controlled trials of oral
medications often included extensive information on side effects. Thus,
accurate comparison of the relative risks of side effects and complications of
different assessment and treatment methods was not possible. Both clinicians and
patients need to consider relative costs of assessment and treatment methods
before making informed decisions about care. Costs vary greatly, however, and
the cost data on assessment and treatment methods for low back problems are
limited. The unit cost of a service may vary within and between geographical
regions. The aggregate cost of services also varies depending on the frequency
and duration of services for the individual patient. Although costs of various
medical services have generally increased in recent years, they have done so
at inconsistent rates. Given these variations, the panel decided to make broad
statements about whether methods appeared to be of low, moderate, or high
cost, graded according to the following system (based on 1993 dollars):
Low cost: under $200. Moderate cost: $200 to $1,000. High cost: over $1,000.
This grading system provides no more than
a rough comparison of costs, and the panel recognized that the divisions
between cost categories are somewhat arbitrary. For example, some Americans may
not consider a $199 expense that comes directly out of pocket to be "low
cost." To develop recommendations for each assessment and
treatment method, the panel considered: (1) the quality and amount of evidence
for efficacy, (2) the strength of the effect found for the method, (3) the
consistency of findings between studies, (4) the clinical applicability of the
evidence to adult patients with acute low back problems, and (5) any evidence
on harms or costs. For each assessment and treatment method the panel then
sought to answer the following questions:
What is the likelihood that this assessment or treatment method will:
Benefit the patient? Harm the patient? Does the likelihood and magnitude of potential benefit outweigh the
likelihood and magnitude of potential harm enough to justify the cost for this
method?
The development of findings and recommendations
statements required the collective judgment of the panel in interpreting the
available evidence. The panel rated the amount and quality of evidence
supporting each guideline statement using the scale in the
Figure below.
= Strong research-based evidence (multiple relevant and
high-quality scientific studies). = Moderate research-based evidence (one relevant, high-quality scientific
study or multiple adequate scientific studies*). = Limited research-based evidence (at least one ade quate scientific study
in patients with low back pain). = Panel interpretation of information that did not meet inclusion
criteria as research-based evidence.
Purpose and Rationale
A second reason for a guideline on assessment and treatment of acute low
back problems is cost. Low back problems are expensive. Their total costs to
society are difficult to calculate, but evidence indicates that both the
economic and psychosocial costs are substantial. Low back problems are the
second most common symptomatic reason expressed by patients for office visits
to primary care physicians.
[5] They are
the most common reason for office visits to orthopedic surgeons,
neurosurgeons, and occupational medicine physicians. They rank third among the
reasons for surgical procedures.
Moreover, although medical costs are
high, loss of time from work as well as the disability payments for
work-related low back problems can together cost up to three times as much as
medical treatment.
[6] About 2
percent of the U.S. work force has compensable back problems each year.
[7] Various
estimates of the total annual societal cost of back pain in the United States
range from $20 to $50 billion.
[8]
Nonmonetary costs of low back problems can also be substantial. The inability
to function normally at work and in other daily activities has an impact on
both patients and their families.
A third important reason for this
guideline is the increasing evidence that many patients with activity
intolerance due to low back symptoms may be receiving care that is
inappropriate or at least less than optimal. Rates for hospitalization and
surgery for low back problems vary substantially among regions of the United
States as well as among small areas within states.
[9]-[11] Marked
regional variations also occur in the use of diagnostic tests for assessing
low back problems.
[9] These
variations imply a lack of consensus about appropriate assessment and
treatment of low back problems, suggesting that some patients may be receiving
inappropriate or suboptimal care.
In addition, some patients appear to
be more disabled after treatment than before, another potential indicator of
suboptimal care. Perhaps the most obvious examples involve surgery. Despite an
extensive medical literature on failed back surgery and evidence that repeat
surgical procedures for low back problems rarely lead to improved outcome,
there are documented examples of patients who have had as many as 20 spine
operations. [9] However, surgery is not the only treatment that can lead to increased
disability. Common treatment methods such as extended bed rest or extended use
of high-dose opioids can prolong symptoms and further debilitate patients.
A fourth reason for the guideline is a growing body of research on low
back problems, allowing a systematic evaluation of commonly used assessment
and treatment methods. Although the existing literature has shortcomings,
there is sufficient scientific evidence for a number of conclusions about the
efficacy and safety of current assessment and treatment methods. Scope and Organization
Scope
In determining the scope of
the guideline, the panel focused on information needed for primary care
assessment and treatment of adults with acute low back problems. "Back
problems" were defined as activity intolerance due to back-related symptoms
and acute as limitations of less than 3 months' duration. Back symptoms include
pain in the back as well as back-related leg pain (sciatica). The panel agreed
that the guideline should provide information on initial detection of
underlying serious conditions (such as fracture, tumor, infection, or cauda
equina syndrome) that could be causing low back problems, but that treatment
of these conditions is outside the scope of the guideline.
The panel
agreed further that the assessment and treatment of patients who have chronic
low back problems (with symptoms lasting over 3 months) may be quite different
than for patients with acute problems. Patients who become disabled due to
chronic low back problems represent less than 5 percent of those with low back
problems, but they account for up to 60 percent of the societal costs for this
disorder. [6] To a much greater extent than acute problems, chronic low back problems
are influenced by complex psychological, behavioral, socioeconomic,
demographic, legal, and occupational factors, many of which are not easily
controlled. [8] For these reasons, the panel decided that chronic low back problems are
beyond the scope of a guideline on acute problems. The recommendations included
in the guideline may not apply to persons younger than 18 years since
diagnostic and treatment considerations for this group are often different
than for adults.
Evaluation of Evidence.
The panel considered
randomized controlled trials (RCTs) that focused on patient-oriented clinical
outcome measures such as symptom relief or improved level of functioning to be
the acceptable method for establishing the efficacy of treatment methods.
Evidence about efficacy of assessment methods was considered adequate if
results of the diagnostic test studied were compared to an independent
reference standard in a way that allowed calculation of standard test
parameters, such as the test's true-positive rate (sensitivity) and
true-negative rate (specificity).
The panel agreed to give the greatest
weight to scientific research evidence that met the above criteria. When such
strong scientific evidence was not available, the panel labeled the evidence
as weak and indirect and used the combined expert opinion and clinical
judgment of panel members for interpretation. In all cases, the guideline
explicitly states the type of evidence used by the panel as the basis for
recommendations. The scale used for labeling the evidence is at the end of this
chapter. Prevention Studies.
The panel
agreed that a methodological problem commonly associated with studies of the
prevention of back problems is lack of precision in specifying the goal(s) of
the preventive intervention. Researchers often fail to establish whether the
goal is to prevent the first episode of low back symptoms, activity
limitations, recurrent episodes, injury claims, time lost from work, chronic
disability, and/or medical care utilization and costs. In addition, some
authors have suggested that efforts to prevent first or recurrent episodes of
low back symptoms at work may be futile, and that research should focus
instead on preventing long-term disability that results in high-cost
disability claims.
[6],
[12],
[13] Organization and Clinical Categories
The panel recognized that different clinical disciplines use a variety of
diagnostic labels that implicitly suggest a cause for low back symptoms.
However, these labels are often unreliable for categorizing causes of acute
low back problems. Even after an extensive workup, only about 15 percent of
patients can be given a definitive diagnosis.
[16]
Since the many diagnostic labels currently used to describe low back
problems may confuse patients and clinicians, the panel considered it more
useful to classify a patient's acute low back problem into one of three
descriptive clinical categories based on medical history and physical
examination findings:
Methodology for Guideline Development
Formation of the Panel and Staff
More than
200 individuals were nominated. AHCPR selected 23 representing the fields of
biomechanical and spine research, chiropractic care, emergency medicine,
family medicine, internal medicine, neurology, neurosurgery, occupational
health nursing, occupational medicine, occupational therapy, orthopedics,
osteopathic medicine, physical and rehabilitation medicine, physical therapy,
psychology, rheumatology, and radiology.
The panel also included a
consumer representative who had experienced low back problems, but did not
work in the health care field. Several consultants with expertise in spine
research, clinical care of low back problems, clinical epidemiology, and
health economics were appointed to the panel. Two methodologists with
experience in developing clinical practice guidelines were assigned to the
panel by AHCPR. Both methodologists were physicians with MPH degrees, one an
emergency medicine physician and one an internist. The methodologists aided
the panel in determining the scope of the literature search and the criteria
to be used for selecting articles for panel review.
The panel chair
formed a research and support staff that included two physicians: a
spine-fellowship-trained orthopedic surgeon and an
occupational-medicine-trained physician with an MPH degree. National Library
of Medicine representatives aided the staff in retrieving literature. The staff
screened articles and constructed evidence tables for articles according to
panel review criteria. These evidence tables and the original articles were
presented to the panel for review and interpretation. The panel used this
information as the basis for its guideline findings and recommendations. Public Comment and Peer Review
Over 100 peer reviewers were selected based on their expertise
in the care of low back problems. They were asked to evaluate the
comprehensiveness of the literature review as well as the panel's findings and
recommendations. The pilot reviewers who were selected represented a
cross-section of primary care settings including private and group practices,
health maintenance organizations, and occupational medicine clinics. They were
asked to evaluate the practical applicability of the guideline in their own
practice settings by using examples published in the Quick Reference Guide
for Clinicians and by soliciting feedback from patients given the Consumer Version. The panel used comments from peer and pilot reviewers
to guide final revisions of the guideline. Literature Search
The literature search of articles published
after 1984 was performed through the National Library of Medicine. Abstracts
of 10,317 articles which met the search criteria were each independently
evaluated by the orthopaedic surgeon and occupational medicine physician on
the research staff. If either reviewer thought an article might be useful, the
entire article was retrieved. A total of 3,918 articles (38 percent of all
abstracts evaluated) was obtained for further evaluation.
Additional
articles came from panel members, from the open forum process, and from
unsolicited sources. All articles were entered in a comprehensive bibliography,
classified by topic, and screened methodologically to determine if they
contained information that might be useful to the panel. Evaluation of Efficacy
The panel used a standard methodology to identify
and evaluate the best scientific evidence available on the efficacy of each
assessment and treatment method, while focusing on clinical outcomes. This
process included a systematic evaluation of each study's quality and its
clinical applicability to patients with acute low back problems. The panel used
this information to screen all articles, using minimum article selection
criteria for efficacy. Articles meeting these minimum criteria were prioritized
(giving priority to articles of higher quality and clinical applicability),
and data from the higher priority articles were abstracted onto evidence
tables.
The panel then reviewed the available data from both evidence
tables and original articles to decide how much weight to give each study in
developing the findings and recommendations statements for this guideline. The
greatest weight was given to studies of high quality that evaluated adults
with acute low back problems, although few such studies were found.
For
most topics, the quality and clinical applicability of studies reviewed were
limited. Inclusion and exclusion criteria for subjects were often either
incompletely described or so broad that they allowed for wide variations in
age, symptoms, symptom duration, examination findings, prior treatments, and
other potentially confounding factors. Studies often inadequately described
the baseline demographic and clinical characteristics of subjects. Many
studies did not distinguish acute from chronic patients; others failed to
either describe or control for factors known to cause significant variation in
outcome (such as prior back surgery). Certain studies lacked appropriate
statistical analysis or included too few subjects to attain adequate
statistical power. Evaluation of Potential Harms and Costs
Evaluating Harms.
A lack of
published evidence about harms related to specific treatment or assessment
methods does not mean that potential harms do not exist. In many instances, the
side effects and complications of assessment and treatment methods have never
been extensively studied or comprehensively reported. In addition, articles
evaluating newer treatment and assessment methods are often written by
advocates of these methods, who may tend to deemphasize the harms.
The
panel felt it was important for both clinicians and patients to have a sense
of potential harms relative to the potential benefits of these methods.
Therefore, the panel considered information about potential harms from a
variety of sources, including case series, case reports, cross-sectional
surveys, clinical trials, and in some instances studies of patients who did
not have low back problems. Finally, if no specific information was available
from any of these sources, the panel generally considered whether the method
was invasive or carried the potential for an allergic reaction. Evaluating Costs.
Developing the Guideline Recommendations
Panel ratings of available evidence supporting guideline statements
*Met minimal formal criteria for scientific methodology and
relevance to population and specific method addressed in guideline
statement.
2. Initial Assessment Methods
Information about the patient's age, the duration and description of
symptoms, the impact of symptoms on activity, and the response to previous
therapy are important in the care of back problems. (Strength of Evidence =
B.) Inquiries about history of cancer, unexplained weight loss,
immunosuppression, intravenous drug use, history of urinary infection, pain
increased by rest, and presence of fever are recommended to elicit red flags
for possible cancer or infection. Such inquiries are especially important in
patients over age 50. (Strength of Evidence = B.) Inquiries about
signs and symptoms of cauda equina syndrome, such as a bladder dysfunction and
saddle anesthesia in addition to major limb motor weakness, are recommended to
elicit red flags for severe neurologic risk to the patient. (Strength of
Evidence = C.) Inquiries about history of significant trauma relative
to age (for example, a fall from height or motor vehicle accident in a young
adult or a minor fall or heavy lift in a potentially osteoporotic or older
patient) are recommended to avoid delays in diagnosing fracture. (Strength of
Evidence = C.) Attention to psychological and socioeconomic problems
in the individual's life is recommended since such nonphysical factors can
complicate both assessment and treatment. (Strength of Evidence = C.) Use of instruments such as a pain drawing or visual analog scale is an option
to augment the history. (Strength of Evidence = D.) Recording the
results of straight leg raising (SLR) is recommended in the assessment of
sciatica in young adults. In older patients with spinal stenosis, SLR may be
normal. (Strength of Evidence = B.) A neurologic examination
emphasizing ankle and knee reflexes, ankle and great toe dorsiflexion
strength, and distribution of sensory complaints is recommended to document
the presence of neurologic deficits. (Strength of Evidence = B.)
The initial assessment
(Attachment A1)
of a patient with activity intolerance due to acute low back symptoms consists
of a focused medical history, a physical examination, and related decisions. A
careful medical history and physical examination are critical. The primary
purpose is to seek medical history responses or physical examination findings
suggesting a serious underlying condition such as fracture, tumor, infection,
or cauda equina syndrome. These responses or findings are referred to as red
flags. They alert clinicians to the possibility that low back symptoms may be
related to a dangerous condition. However, serious conditions presenting as
low back problems are relatively rare. Of the 214 articles screened for this topic, 34 met the article selection
criteria for efficacy.
[20]-[53] A few key
questions on the medical history can help ensure that a serious underlying
condition, such as cancer
[26] or
spinal infection, will not be missed. These questions include: age, history of
cancer, unexplained weight loss, immunosuppression, duration of symptoms,
responsiveness to previous therapy, pain that is worse at rest, history of
intravenous drug use, and urinary or other infection. The physical
examination supplements the information obtained in the medical history in
seeking an underlying serious condition or possible neurologic compromise. The
basic elements of a physical examination are inspection, palpation,
observation including range of motion testing, and a specialized neuromuscular
evaluation. This evaluation emphasizes ankle and knee reflexes, ankle and great
toe dorsiflexion strength, and distribution of sensory complaints. For
patients presenting with acute low back problems and no limb complaints, a
more elaborate neurologic evaluation is usually not necessary. Potential harms and costs are considered low for both the medical history and
the physical examination. Positive answers to key medical history questions, in
addition to positive findings on physical examination and/or simple lab tests,
are red flags that suggest the possibility of a serious underlying condition
as the cause of acute low back problems.
The initial assessment
categorizes back symptoms without red flags as either primarily back
(nonneurologic) or sciatic (neurologic) and defines the duration of these
symptoms to guide both what type of special studies may be considered and when
they should be considered. In the absence of red flags, special tests are not
usually required in the first month of low back symptoms because most patients
recover from their activity limitations within 1 month.
The initial
assessment also provides an opportunity for the clinician to establish rapport
with the patient, to find out patient expectations, and to become aware of
potential psychological and socioeconomic factors that can alter response to
care. Assessment Literature Reviewed
The important points in these articles are well summarized in review
articles by Deyo, Rainville, and Kent
[54] and
Waddell, Main, Morris, et al.
[55] Both
reviews elaborate on the reproducibility and accuracy of specific medical
history findings (Table 1) and physical examination findings
(Table 2) for
assessing low back problems. Other articles not meeting selection criteria are
cited where appropriate since they contain information used in formulating
recommendations.
[56-65] Evidence on Efficacy of Assessment Methods
Medical History
Symptoms of
sciatica (leg pain) or neurogenic claudication (walking limitations due to leg
pain) suggest possible neurologic involvement. Pain radiating below the knee is
more likely to indicate a true radiculopathy than pain radiating only to the
posterior thigh. A history of persistent numbness or weakness in the leg(s)
further increases the likelihood of neurologic involvement. The articles
indicate that cauda equina syndrome can be ruled out with a medical history
that ascertains the absence of bladder dysfunction (usually urinary retention
or overflow incontinence), saddle anesthesia, and unilateral or bilateral leg
pain and weakness.
Patients' reports of symptoms and treatment
outcomes may be influenced by psychological or socioeconomic factors. Several
studies have reported a variety of such factors for patients with low back
problems. These factors include work status, typical job tasks, educational
level, pending litigation, worker's compensation or disability issues, failed
previous treatments, substance abuse, and depression.
[23],
[38],
[39],
[41],
[43],
[50],
[58]
Clinicians are urged by some authors to augment the medical history with
pain drawings and visual analog pain rating scales to document the
distribution of pain and intensity of symptoms
(Attachment B).
[40],
[45],
[46],
[52],
[53] Physical Examination
The
physical examination is less useful than the history in searching for
underlying serious conditions such as cancer, but may be helpful in detecting
spinal infections. Fever, vertebral tenderness, and very limited spinal range
of motion suggest the possibility of spinal infections, but these are also
common findings in patients without infection. Otherwise, evaluation of spinal
range of motion has been found to be of limited diagnostic value,
[62]
although some clinicians consider it helpful in planning and monitoring
treatment.
Findings from both the history and physical examination
provide useful information in the search for possible neurologic compromise.
For example, sciatica has such a high true-positive rate for lumbar nerve root
compression that its absence makes a clinically important lumbar disc
herniation related to neural compression unlikely. In addition, leg pain
usually overshadows back pain when such a clinically significant radiculopathy
is present. Finally, crossed straight leg raising is such a highly specific
test that a positive finding makes neurologic compromise due to herniated
lumbar disc very likely, but this is not a sensitive test since discomfort
upon crossed straight leg raising may be absent in many patients with
neurologic compression.
[31],
[34],
[61],
[63]
Deyo, Rainville, and Kent's summary
[54] of
available data suggests that in the primary care setting for patients with leg
symptoms, the neurologic examination can safely be limited to a few tests.
These are: (1) testing of dorsiflexion strength of the ankle and the great
toe, with weakness suggesting L5 and some L4 root dysfunction; (2) testing of
ankle reflexes to evaluate S1 root dysfunction; (3) testing of light touch
sensation in the medial (L4), dorsal (L5), and lateral (S1) aspects of the
foot; and (4) the straight leg raising (SLR) test.
This abbreviated
neurologic examination of the lower extremities will allow detection of most
clinically significant nerve root compromise due to L4-L5 or L5-S1 disc
herniations, which together make up over 90 percent of all clinically
significant radiculopathy due to lumbar disc herniations.
[35],
[37],
[56],
[61],
[63]
Although this limited examination might miss the much less common L2-L3 or
L3-L4 disc herniations, these conditions are more difficult to diagnose on
physical examination. Moreover, if such patients have not improved by 1 month,
this guideline suggests a further diagnostic workup or consultation
(Chapter 4), which may clarify the diagnosis. For over 95 percent of patients with
acute low back problems, no special interventions or diagnostic tests would be
required within the first month of symptoms. Potential Harms and Costs of Assessment Methods
Summary of Findings
For cancer or infection, red
flags are: history of cancer, unexplained weight loss, immunosuppression,
urinary infection, intravenous drug use, prolonged use of corticosteroids,
back pain not improved with rest, and age of patient over 50.
For
spinal fracture, red flags are: history of significant trauma (for example, a
fall from a height, motor vehicle accident, or direct blow to the back for a
young adult, or a minor fall or heavy lift in a potentially osteoporotic or
elderly individual), prolonged use of steroids, and age over 70.
For
cauda equina syndrome or severe neurologic compromise, red flags are: medical
history or physical examination findings of acute onset of urinary retention
or overflow incontinence, loss of anal sphincter tone or fecal incontinence,
saddle anesthesia (about the anus, perineum, and genitals), and global or
progressive motor weakness in the lower limbs.
There are indications
in the literature that psychological or socioeconomic factors may affect a
patient's report of symptoms and response to treatment.
Simple
laboratory tests, including complete blood count (CBC) and erythrocyte
sedimentation rate (ESR), are sufficiently inexpensive and efficacious for use
as initial tests when there is suspicion of back-related tumor or infection.
3. Clinical Care Methods
In the absence of red flags, treatment is similar for most patients with
activity intolerance due to an acute episode of low back symptoms
(Attachment A2).
After assuring the patient that there is no hint of a dangerous problem and
that a rapid recovery is expected, the goals are to provide accurate patient
information about low back problems, to help provide comfort by means of
symptom control methods, and to recommend activity modifications.
Expectations for both rapid recovery and recurrence of symptoms based
on natural history of low back symptoms. Safe and effective methods
of symptom control. Safe and reasonable activity modifications. Best means of limiting recurrent low back problems. The lack of
need for special investigations unless red flags are present. Effectiveness and risks of commonly available diagnostic and further treatment
measures to be considered should symptoms persist.
Patient education as defined here includes all forms of
patient-oriented education about low back problems except for "back schools"
(formally structured, classroom-style back education programs). Under this
definition, patient education includes printed and audiovisual materials,
information given by health care providers, and educational programs that are
less formal than back schools. Of 14 articles screened for this topic, 2 met the
criteria for review.
[67],
[68] Other
articles contained information used by the panel, but did not meet article
selection criteria.
[69]-
[71] Jones,
Jones, and Katz
[67]
evaluated educational intervention for patients with low back problems who
came to a hospital emergency department and were referred for followup care.
Patients receiving an educational intervention in the emergency department
and/or a followup phone call were more likely than control patients to
schedule and keep their followup appointment. The potential risks, harms, and costs of educating patients are considered
to below. Evidence indicates that educating patients about back problems may
reduce use of medical resources, decrease patient apprehension, and speed
recovery. In the workplace, back schools with worksite-specific
education may be effective adjuncts to individual education efforts by the
clinician in the treatment of patients with acute low back problems. (Strength
of Evidence = C.) The efficacy of back schools in nonoccupational
settings has yet to be demonstrated. (Strength of Evidence = C.)
Back school is defined here as a structured program of
education about low back problems, usually in a group setting. The therapeutic
objectives are to give the patient information on the anatomy and natural
history of disorders of the back; to teach the principles underlying posture,
daily activities, and sports; and thereby to increase functional work
capacity. Of 35 articles screened for this topic, 15 reporting on 12 RCTs met criteria
for review. [72]- [86] One of the few studies demonstrating the efficacy of back school
[72] was
conducted in the medical department of a Swedish automotive assembly plant.
The 217 subjects all had nonspecific low back pain for less than 3 months and
were randomly assigned to one of three interventions: back school, combined
physiotherapy exercise, or placebo shortwave diathermy. The back school
intervention consisted of four 45-minute sessions in 2 weeks and included the
following topics: anatomy and causes of low back problems, muscle function and
posture, ergonomics, and advice on physical activity. Patients attending back
school had a shorter duration of sick leave during the initial episode than
the other two treatment groups, but at the 1-year followup neither the number
nor the length of absences from work owing to recurrences differed among the
three treatment groups. The potential risks
and harms of back schools are considered low. Costs are variable, depending on
the number of sessions and the setting, and range from moderately inexpensive
to expensive. Available data on formal patient education programs, or back schools,
vary in terms of program quality, length, content, costs, and outcomes. Only
one study of a structured low back education program, performed in industry,
was found to have a positive short-term impact on acute low back problems
although no effect was seen at 1-year followup.
[72] In
summary, the published evidence on back school as a treatment for acute low
back problems is limited in quantity and the results are contradictory. Symptom control methods focus initially on providing comfort to keep the
patient as active as possible while awaiting spontaneous recovery and, later
in treatment, on aiding the activation needed to overcome a specific activity
intolerance. The methods traditionally include oral medications, such as
acetaminophen and nonsteroidal anti-inflammatory drugs (NSAIDs), as well as
physical treatments. They also include therapeutic injections. Proving the
efficacy of these methods to relieve acute low back symptoms is difficult due
to the rapid rate of spontaneous recovery. The use of symptom control methods
known to have less risk of harm than methods with proven efficacy may thus be
warranted if such methods are inexpensive and allow an individual to remain
active or build activity tolerance through exercise. Acetaminophen is reasonably safe and is
acceptable for treating patients with acute low back problems. (Strength of
Evidence = C.) Nonsteroidal anti-inflammatory drugs (NSAIDs),
including aspirin, are acceptable for treating patients with acute low back
problems. (Strength of Evidence = B.) NSAIDs have a number of
potential side effects. The most frequent complication is gastrointestinal
irritation. The decision to use these medications can be guided by comorbidity,
side effects, cost, and patient and provider preference. (Strength of Evidence
= C.) Phenylbutazone is not recommended, based on an increased risk
for bone marrow suppression. (Strength of Evidence = C.)
Acetaminophen, a nonnarcotic analgesic, has commonly been regarded as
having an analgesic effect, but little or no known anti-inflammatory
mechanism. The therapeutic objective for its use in acute low back problems is
pain relief. Muscle relaxants are an option in the treatment of
patients with acute low back problems. While probably more effective than
placebo, muscle relaxants have not been shown to be more effective than
NSAIDs. (Strength of Evidence = C.) No additional benefit is gained by
using muscle relaxants in combination with NSAIDs over using NSAIDs alone.
(Strength of Evidence = C.) Muscle relaxants have potential side
effects, including drowsiness in up to 30 percent of patients. When
considering the optional use of muscle relaxants, the clinician should balance
the potential for drowsiness against a patient's intolerance of other agents.
(Strength of Evidence = C.)
Muscle relaxants are
commonly used for the treatment of low back problems. Pharmacologically, these
are usually benzodiazepines, other sedative medications, or antihistamine
derivatives. The therapeutic objective of muscle relaxants is to reduce low
back pain by relieving muscle spasm. However, the concept of skeletal muscle
spasm is not universally accepted as a cause of symptoms, and the most
commonly used muscle relaxants have no peripheral effect on muscle spasm. When used only for a time-limited course, opioid analgesics are an option in
the management of patients with acute low back problems. The decision to use
opioids should be guided by consideration of their potential complications
relative to other options. (Strength of Evidence = C.) Opioids appear
to be no more effective in relieving low back symptoms than safer analgesics,
such as acetaminophen or aspirin or other NSAIDs. (Strength of Evidence = C.) Clinicians should be aware of the side effects of opioids, such as
decreased reaction time, clouded judgment, and drowsiness, which lead to early
discontinuation by as many as 35 percent of patients. (Strength of Evidence =
C.) Patients should be warned about potential physical dependence and
the danger associated with the use of opioids while operating heavy equipment
or driving. (Strength of Evidence = C.)
Oral
opioid analgesics commonly given to patients with acute low back problems
include morphine derivatives (opioids) and synthetic opioids. The therapeutic
objective in treating low back problems is temporary pain relief. Oral steroids are not recommended for the treatment
of acute low back problems. (Strength of Evidence = C.) A potential
for severe side effects is associated with the extended use of oral steroids
or the short-term use of steroids in high doses. (Strength of Evidence = D.) Oral steroids (corticosteroids) are used by some
clinicians in the treatment of patients with acute low back problems. The
therapeutic objective is to reduce inflammation in an attempt to promote
healing and reduce pain. Colchicine has been used
primarily to treat acute attacks of gouty arthritis and can be administered
intravenously or orally. The therapeutic objective of using the drug in
patients with acute low back problems is to reduce inflammation and thereby
reduce pain. Antidepressant medications have been widely used for both depressed and
nondepressed patients with chronic low back problems. The extent to which
these medications are used in treating patients with acute low back problems
is unknown. Some researchers have hypothesized that the medications may
possibly have a pain-relieving effect in addition to antidepressant
properties. If so, the medications could help some patients who have chronic
pain whether or not the patients are also depressed. The therapeutic objective
of using antidepressant medications for low back problems is to reduce pain. Manipulation can be helpful for patients with acute
low back problems without radiculopathy when used within the first month of
symptoms. (Strength of Evidence = B.) When findings suggest
progressive or severe neurologic deficits, an appropriate diagnostic
assessment to rule out serious neurologic conditions is indicated before
beginning manipulation therapy. (Strength of Evidence = D.) There is
insufficient evidence to recommend manipulation for patients with
radiculopathy. (Strength of Evidence = C.) A trial of manipulation in
patients without radiculopathy with symptoms longer than a month is probably
safe, but efficacy is unproven. (Strength of Evidence = C.) If
manipulation has not resulted in symptomatic improvement that allows increased
function after 1 month of treatment, manipulation therapy should be stopped
and the patient reevaluated. (Strength of Evidence = D.) Physical agents and modalities include ice,
heat (including diathermy), massage, ultrasound, cutaneous laser treatment,
and electrical stimulation (not transcutaneous electrical nerve stimulation or
TENS). The therapeutic objective of physical agents and modalities is to
provide symptomatic relief and, for some modalities, to reduce inflammation,
"muscular symptoms," or joint stiffness. A TENS unit is a small battery-operated
device worn by the patient. It provides continuous pulses of electricity by way
of surface electrodes. Presumably, TENS produces a counter-stimulation of the
nervous system, which can modify pain perception. The therapeutic objective of
TENS in patients with low back problems is to provide symptomatic pain
relief. Shoe insoles may be effective for
patients with acute low back problems who stand for prolonged periods of
time. Given the low cost and low potential for harms, shoe insoles are a
treatment option. (Strength of Evidence = C.) Shoe lifts are not
recommended for treatment of acute low back problems when lower limb length
difference is <=2 cm. (Strength of Evidence = D.)
Shoe insoles (or inserts) are devices placed inside shoes that may vary
from over-the-counter foam or rubber inserts to custom-made orthotics. The
therapeutic objective of shoe inserts is the reduction of back pain. Lumbar corsets and support belts have not been proven beneficial for treating
patients with acute low back problems. (Strength of Evidence = D.) Lumbar corsets, used preventively, may reduce time lost from work due to low
back problems in individuals required to do frequent lifting at work.
(Strength of Evidence = C.) Lumbar support devices
for low back problems include lumbar corsets and support belts, back braces
and molded jackets, and back rests for chairs and car seats. The panel decided
to evaluate only lumbar corsets and support belts for this guideline. Among
theories on why lumbar corsets and support belts might help treat or prevent
low back problems are that they compress the abdomen (causing increased
intra-abdominal pressure, which unloads the vertebral column) and/or that they
act as a mechanical reminder to decrease bending. Therapeutic objectives of
lumbar supports are to control pain and/or protect against injury. Traction, when used for low back problems, involves
the application of intermittent or continuous force along the axis of the
spine in an attempt to elongate the spine by either mechanical or manual
means. The most common type used for low back pain is pelvic traction, in which
a snug girdle around the pelvis is attached to weights hung at the foot of the
bed. The therapeutic objective of traction for patients with low back problems
is to reduce pain. Biofeedback involves translating the physiologic
activity of a patient's muscular response into a visual or auditory signal
that allows the patient to try to facilitate or inhibit the muscular
activity. The therapeutic objective is to reduce muscle tension and thereby
reduce pain. Biofeedback has been advocated primarily for patients with chronic
low back problems. Trigger point injections are invasive and not recommended in the treatment of
patients with acute low back problems. (Strength of Evidence = C.) Ligamentous and sclerosant injections are invasive and not recommended in the
treatment of patients with acute low back problems. (Strength of Evidence =
C.) Trigger point injections involve the
injection of local anesthetic into soft tissues (muscles) near localized
tender points in the paravertebral area.
[189] The theory that such trigger points are responsible for causing or
perpetuating low back pain is controversial and disputed by many experts.
Other articles reviewed for this topic involve the injection of various
substances (especially sclerosing agents) into interspinal ligaments and
ligamentous muscle attachments in the low back. The theory behind such
treatment is that this stimulates formation of scar tissue in ligaments. The
therapeutic objective of both trigger point injections and ligamentous
injections is to reduce low back pain. In treatment of low back problems, facet
joint injections involve the injection of local anesthetics and/or
corticosteroids into or around facet joints of the lumbar spine, with needle
placement aided by fluoroscopy. The theoretical basis is that some patients
with low back problems have a "facet syndrome" with pain arising from facet
joints. The facet syndrome reportedly involves patients with primarily low back
pain (unilateral or bilateral) and no root tension signs or neurologic
deficits, the pain usually being aggravated by extension of the spine.
[191] The therapeutic objective of facet joint injections is temporary
relief from motion-limiting pain so the patient may proceed into an
appropriate exercise program.
[198] There is no evidence to support the use of
invasive epidural injections of steroids, local anesthetics, and/or opioids as
a treatment for acute low back pain without radiculopathy. (Strength of
Evidence = D.) Epidural steroid injections are an option for
short-term relief of radicular pain after failure of conservative treatment
and as a means of avoiding surgery. (Strength of Evidence = C.) Acupuncture is defined here to include all types of "dry
needling" procedures (where no medication is injected) into cutaneous and
subcutaneous tissues, muscles, or ligaments. Traditional acupuncture, based on
Chinese philosophy, requires that needles be inserted into specific areas of
the body (the prescribed Chinese meridians) and that these needles be rotated
to produce a noxious stimulus. Other types of dry needling involve needle
insertion without regard for the Chinese meridians into tender spots or other
areas and may or may not involve the rotation of the needles. Some dry
needling techniques also add electrical stimulation to the needles. The
therapeutic objective of acupuncture and other dry needling techniques is to
reduce pain. Patients with acute low back problems may be more
comfortable if they temporarily limit or avoid specific activities known to
increase mechanical stress on the spine, especially prolonged unsupported
sitting, heavy lifting, and bending or twisting the back while lifting.
(Strength of Evidence = D.) Activity recommendations for the employed
patient with acute low back symptoms need to consider the patient's age and
general health, and the physical demands of required job tasks. (Strength of
Evidence = D.) Patients with acute low back
problems frequently seek advice from clinicians about the physical activities
they can "safely" perform. Employed patients, or their employers, also often
ask health care providers to recommend work restrictions that will allow the
patient to remain on the job during an episode of acute low back symptoms.
Activity modifications are aimed at allowing the patient with an acute low
back problem to achieve a tolerable comfort level while continuing adequate
physical activity to avoid debilitation. The overall goal is to aid recovery
while disrupting daily activities as little as possible. Of the articles screened dealing with work and
other activity modifications for patients with acute low back problems, none
met established panel review criteria for adequate evidence about efficacy.
However, eight articles were considered by the panel to contain useful
information on these issues.
[221]-
[228] A number of epidemiological
studies have looked at risk factors associated with developing acute low back
problems. Although there is no clear consensus on the role of these factors,
several studies have identified an increased incidence of low back problems
among individuals whose work involves heavy or repetitive lifting, exposure to
total body vibration (from vehicles or industrial machinery), asymmetric
postures, and postures sustained for long periods of time.
[222],
[225] While scientific information is
limited, the panel felt that activity modifications represented an important
practical issue for the clinician. The panel's recommendations are based on
their interpretation of the available scientific data. Patients with acute low
back problems can be advised to limit temporarily any heavy lifting, prolonged
sitting, and bending or twisting the back since these activities have been
shown to increase mechanical stress on the spine. A gradual return to normal activities is
more effective than prolonged bed rest for treating acute low back problems.
(Strength of Evidence = B.) Prolonged bed rest for more than 4 days
may lead to debilitation and is not recommended for treating acute low back
problems. (Strength of Evidence = B.) The majority of low back
patients will not require bed rest. Bed rest for 2 to 4 days may be an option
for patients with severe initial symptoms of primarily leg pain. (Strength of
Evidence = D.) Bed rest is a frequently used
treatment for acute low back pain. The therapeutic objective is to relieve
symptoms by reducing intradiscal pressure and/or pressure on nerve roots.
Studies have shown that intradiscal pressures are lowest when subjects are
lying supine in the semi-Fowler position, on the back with hips and knees
moderately flexed.
[8] Of 12 articles screened for this topic,
5 reporting on 4 RCTs met criteria for review.
[75],
[85],
[117],
[229],
[230] All
these studies evaluated patients with acute low back problems. Other articles
contained information used by the panel, but did not meet selection criteria.
[8],
[231],
[232] Evidence is limited regarding
efficacy of bed rest versus no treatment for patients with acute low back
problems. One study involving military recruits compared forced bed rest to an
alternative treatment of forced ambulation.
[117]
Although the bed rest group returned to full activity sooner, methodological
problems with this study made interpretation difficult. Outcome assessments
were not blinded, and patients in the hospitalized group were deprived of
their peer-group activities, possibly confounding results. Two articles
compared groups receiving either a recommendation for bed rest (of at least 4
days duration) or some other treatment (such as exercise, education, or
manipulation) but no bed rest recommendation.
[75], [85], [230] These two articles found no statistically significant differences
between bed rest and other treatment modalities. Bed rest of more than 4 days
and the resulting deactivation were worse for patients than a gradual return
to normal levels of activity. Deyo, Diehl, and Rosenthal
[229]
compared two groups receiving recommendations for either 2 days or 7 days of
bed rest. No differences were found between the groups in pain relief or in
time to resumption of normal activities, except for earlier return to work in
the 2-day group for those employed at baseline. Potential physical side effects from prolonged bed rest are many,
including muscle atrophy (1.0 to 1.5 percent of muscle mass lost per day),
cardiopulmonary deconditioning (15-percent loss in aerobic capacity in 10
days), bone mineral loss with hypercalcemia and hypercalciuria, and the risk
of thromboembolism.
[232] There are also social side effects, such as perception of severe
illness and economic loss due to increased time lost from work.
[231] There is no
evidence to support the efficacy of bed rest compared with no treatment in
patients with acute low back problems. Deactivation resulting from prolonged
bed rest (more than 2 to 4 days) appears to be worse for patients than a
gradual return to normal levels of activity. Low-stress aerobic exercise can prevent debilitation due to
inactivity during the first month of symptoms and thereafter may help to
return patients to the highest level of functioning appropriate to their
circumstances. (Strength of Evidence = C.) Aerobic (endurance)
exercise programs, which minimally stress the back (walking, biking, or
swimming), can be started during the first 2 weeks for most patients with
acute low back problems. (Strength of Evidence = D.) Conditioning exercises for
trunk muscles (especially back extensors), gradually increased, are helpful
for patients with acute low back problems, especially if symptoms persist.
During the first 2 weeks, these exercises may aggravate symptoms since they
mechanically stress the back more than endurance exercises. (Strength of
Evidence = C.) Back-specific exercise machines provide no apparent
benefit over traditional exercise in the treatment of patients with acute low
back problems. (Strength of Evidence = D.) Evidence does not support
stretching of the back muscles in the treatment of patients with acute low
back problems. (Strength of Evidence = D.) Recommended exercise quotas
that are gradually increased result in better outcomes than telling patients
to stop exercising if pain occurs. (Strength of Evidence = C.) Various types of exercise programs have been advocated for
patients with low back problems. The most commonly studied types focus on back
flexion, back extension, generalized strengthening, endurance (aerobic
conditioning), stretching, or some combination of these. Authors also reported
exercises for low back problems as dynamic (isotonic) and static (isometric).
Most of these exercises can be either taught to the patient for home use or
performed under supervision in a clinical setting. Commonly reported
therapeutic objectives of exercise programs for low back problems are
improvements in endurance, muscle strength, and flexibility presumably leading
to reduced symptoms, improved level of functioning, and fewer or less severe
future back problems. Of 92
articles screened, 20 RCTs met criteria for review.
[74], [75], [81]
, [83],
[84],
[86],
[131],
[155],
[157],
[233] -
[243] Of the six articles evaluating patients with
acute low back problems, only one was considered well designed.
[83]
Swedish auto workers who had been off work for 6 weeks due to low back
problems were randomized to either a control group with no recommendations for
exercise or an exercise group with a program of gradually increased aerobic
and back-strengthening exercises. At 1-year followup, patients in the exercise
group had lost significantly less time from work due to back pain and had
achieved a significantly higher level of fitness compared with the control
group. Potential harms of exercise are usually not
discussed. However, one RCT found that extension exercises caused increased
symptoms in chronic low back pain patients.
[238]
Another study suggests that abdominal flexion (Williams flexion) exercises and
stretching can increase mechanical stress on the spine as observed by
intradiscal pressure measurements.
[248] There are only a
few RCTs that have evaluated exercise as a treatment for acute low back
problems, and these are limited by small numbers of patients and inadequate
descriptions of specific exercise regimens. The one well-designed RCT of
patients limited for less than 3 months by low back symptoms found that a
program of gradually increased aerobic and back-strengthening exercises was
superior to doing no exercise at all.
[83] Patient Information
Patient Education About Low Back Symptoms
Panel findings and recommendations:
Literature Reviewed.
Neither of the studies meeting the criteria focused solely on patients with
acute low back problems. Both evaluated patients with low back problems of
unspecified duration. Interventions evaluated included giving patients booklets
on back pain [68] and holding a brief individual educational session during an emergency
room visit or by phone after the visit.
[67] Evidence on Efficacy.
Roland and Dixon
[68]
conducted a randomized controlled trial (RCT) in which patients presenting
with low back problems were assigned either to a group receiving an
educational booklet on back problems or to a control group receiving no
educational materials. In the first 2 weeks after the intervention, no
differences were found between the education and control groups in number of
consultations for back pain. However, in the period from 2 weeks to 1 year
after the intervention, significantly fewer patients in the group receiving
the booklet consulted physicians for back pain.
The importance of
providing information to the patient is indicated in a study by Deyo and
Diehl. [70] Failure to receive an explanation of the problem was the most frequently
cited source of patient dissatisfaction among 140 patients with low back
problems. Patients who felt they did not receive an adequate explanation wanted
more diagnostic tests, were less satisfied with their visit, and were less
likely to want the same doctor again, compared with patients who reported an
adequate explanation.
Thomas
[71]
randomly assigned patients with symptoms (including low back pain), but no
definite diagnosis, to one of four consultations: either one of two positive
consultations, with and without treatment, or one of two negative
consultations, with and without treatment. In the positive consultations,
patients were given a firm diagnosis and told confidently that they would be
better in a few days. The negative consultations were devised so that no firm
assurance was given. Two weeks later the difference in recovery was significant
between the positive and negative groups, but not between the treated and
untreated groups.
A study of patients visiting family physicians for
common symptoms, including back or neck pain, found that gaining patient
agreement about the nature of the problem led to earlier resolution.sup]69 Potential Harms and Costs.
Summary of Findings.
Structured Patient Education: Back School
Panel findings and recommendations:
Literature Reviewed.
Two meta-analyses regarding back schools were also examined.
[87,
88] The
panel used information from one other study that did not meet selection
criteria. [89] Evidence on Efficacy.
A meta-analysis by Keijsers, Bouter, and
Meertens [87] evaluated eight studies of back schools done in group settings.
[72,
73,
76,
79,
81,
85,
86,
89] These
studies of back schools were compared in terms of program duration and
content, patient selection criteria, number of patients, interventions, and
outcome measures used. All eight studies were found to have major
methodological problems. The authors found that although there was insufficient
evidence to form a strong and valid judgment on the efficacy of back schools,
the available evidence suggested that back schools are at most marginally
effective.
Another meta-analysis by Linton and Kamwendo
[88]
reviewed the scientific literature on back schools and reported some positive
effects in studies of patients with acute back pain. However, the authors
found that most studies of back schools lacked adequate control groups and
that the evidence on efficacy is inconclusive. Potential Harms and Costs.
Summary of Findings.
Symptom Control Methods
Symptom Control: Medications
Acetaminophen and NSAIDs
Panel findings and recommendations:
NSAIDs are a class of medications, including aspirin,
ibuprofen, indomethacin, phenylbutazone, and a variety of other drugs. They
have anti-inflammatory and analgesic properties as well as being prostaglandin
inhibitors. The therapeutic objective of NSAIDs in treating acute low back
problems is to decrease pain, presumably by reducing inflammation and
promoting healing.
Literature Reviewed.
Of 50 articles
screened for this topic, 4 RCTs met the review criteria for adequate evidence
about efficacy.
[85],
[90] -
[92] Other
articles did not meet the criteria, but contained information used by the
panel. [93]- [103]
Evidence on Efficacy.
The four RCTs that
met review criteria for this topic were all double-blind studies comparing
NSAIDs with a placebo in treating patients with low back problems. No studies
were found that compared acetaminophen to placebo in treatment of patients
with low back pain.
Two studies compared a single NSAID to a placebo:
Amlie, Weber, and Holme
[90]
evaluated piroxicam. Postacchini, Facchini, and Palieri
[85]
evaluated diclofenac. The study by Berry, Bloom, Hamilton, et al.
[92] had
three treatment groups evaluating either one of two NSAIDs (diflunisal or
naproxen sodium) or a placebo. The study by Basmajian
[91]
compared four treatment groups receiving an NSAID alone (diflunisal), a muscle
relaxant alone (cyclobenzaprine), the two in combination, or a placebo.
Three of the studies evaluated patients with acute low back symptoms of less
than 3 months' duration.
[85],
[90],
[91]
Berry, Bloom, Hamilton, et al.
[92]
evaluated patients with chronic low back pain.
Three studies found
NSAIDs superior to a placebo for pain relief in the short term: from 1 week to
2 months of symptom duration.
[85,
90,
92] The
remaining study found no significant difference between NSAID and placebo in
terms of pain improvement scores.
[91]
Although there were no RCTs comparing acetaminophen to placebo for patients
with low back pain, one nonplacebo-controlled RCT found an NSAID (diflunisal)
superior to paracetamol (which is similar to acetaminophen) in producing pain
relief for patients with chronic low back pain.
[97] In
addition, the literature on acetaminophen does show it to be more effective
than placebo in studies of patients with nonback-related pain.
[98],
[102]
Several RCTs comparing efficacy of different NSAIDs in the same study have
found no NSAID to be consistently more effective than the others.
[96,
101,
102]
However, these studies also suggest that individual patients report better
pain relief from some NSAIDs compared with others. For this reason, Brooks and
Day [93]
suggest that patients change to a different NSAID if no relief is reported
after a 2-week trial. Potential Harms and Costs.
The risks from the use of acetaminophen at usual doses are low.
[95]
However, high doses of acetaminophen can lead to liver damage, and massive
single doses sometimes lead to fatal hepatic necrosis. Compared with NSAIDs,
acetaminophen has a minimal effect on platelets and few gastrointestinal side
effects since it is not a mucosal irritant. Acetaminophen is inexpensive. The
expense of treatment with NSAIDs varies greatly, depending on the medication
used and the length of treatment.
Potential complications of NSAIDs
have been extensively studied.
[93],
[95] These
include gastritis and other gastrointestinal complaints, including bleeding in
20 to 30 percent of those patients with active peptic ulcer problems. The
degree of gastrointestinal side effects from NSAIDs appears to be dose
related, but side effects can occur with one tablet. Ingestion of NSAIDs with
meals or in combination with antacids has not been proven effective in
reducing these gastrointestinal side effects. However, one medication
(misoprostol), when taken with NSAIDs, has been shown to reduce NSAID-induced
gastric erosion and the risk for gastroduodenal ulcers.
[99],
[100]
NSAIDs interfere with platelet adhesion and renal sodium metabolism. Their
use in patients with a bleeding diathesis is considered contraindicated. They
can be used in the presence of hypertension, renal disease, and edematous
states, but only if great caution is exercised.
[93] For
these reasons, some experts caution that routine blood tests (such as CBC and
serum chemistry screen) be done before treatment for older patients or those
with vascular disease. These tests are also recommended if there is any
suspicion of complications for those patients on prolonged NSAID therapy.
[95]
Phenylbutazone has been associated with bone marrow suppression (aplastic
anemia and agranulocytosis). Indomethacin has a higher reported incidence of
gastrointestinal side effects than other NSAIDs. Otherwise, there is no
significant demonstrated difference between remaining NSAID preparations in
terms of the prevalence or severity of complications.
[95] Summary of Findings.
There is fair to good evidence
that NSAIDs are effective for reducing pain in patients with acute low back
problems. Although no studies were found comparing acetaminophen to placebo in
patients with back pain, there is evidence that acetaminophen is comparable in
efficacy to NSAIDs for treating back problems and with fewer side effects. In
studies of patients with nonback pain, no consistent difference in symptom
relief has been demonstrated between acetaminophen and any available NSAID
(including aspirin). Both NSAIDs and acetaminophen have been found to be
generally adequate to achieve pain relief. Muscle Relaxants
Panel findings and recommendations:
Literature Reviewed.
Of 42 articles screened for this
topic, 12 RCTs met review criteria for adequate evidence about efficacy.
[91,
[104-
114] Evidence on Efficacy.
Three studies evaluating
patients with low back problems either did not specify duration of symptoms or
included a mix of patients with acute and chronic problems.
[104,
113,
114] The
remaining nine studies evaluated only patients with acute low back problems.
Of the articles that met review criteria, 9 evaluated a muscle relaxant
compared with a placebo.
[91,
104,
105,
108-
113] Two
studies compared two different muscle relaxants.
[107],
[114] Some
of the studies also compared a muscle relaxant to another medication,
including a barbiturate;
[110],
[111] an
NSAID; [91], [106] and acetaminophen.
[91]
Of the nine studies comparing muscle relaxants with placebos, seven had
results favoring the muscle relaxant.
[104],
[105],
[108] -
[111],
[113] Two
showed no difference in outcomes between muscle relaxant and placebo.
[91],
[112] In
most studies, the positive effect for muscle relaxants was short-lived,
lasting no more than 4 to 7 days, with no significant difference from placebo
seen after this time.
Panel methodologists did a meta-analysis of the
12 studies that met panel review criteria. The studies were assessed for
quality without knowledge of the results. There was one excellent study,
[107]
three good studies,
[105],
[109],
[114] and
eight fair studies.
[91],
[104],
[106],
[108],
[110] -
[113]
Each study was examined for outcome measures such as pain, functional
capacity, or a global measure of improvement. When meta-analytically combined,
the studies showed a trend toward greater improvement in the patients treated
with muscle relaxants, but did not reach statistical significance. Even if the
findings had reached significance, statistical combinations of such study
results should be interpreted with caution. The conclusion of the meta-analysis
was that muscle relaxants are probably, but not certainly, more effective than
placebos in decreasing symptoms of acute low back problems. However, there was
not enough evidence to determine whether muscle relaxants are more or less
effective than NSAIDs for reducing symptoms or whether the addition of a
muscle relaxant adds to the efficacy of an NSAID. Potential Harms and Costs.
Potential complications of muscle relaxants
include drowsiness and dizziness, reported to be up to 30 percent higher in
patients taking muscle relaxants compared with patients taking placebos.
[91],
[104],
[105],
[108] -
[113] The
cost of muscle relaxants is considered low to moderate. Summary of Findings.
There is moderate research evidence that muscle
relaxants are more effective than placebo, but no evidence that they are
better than NSAIDs, in relieving symptoms of acute low back problems. These
medications have substantial potential side effects, especially a high
incidence of drowsiness. Opioid Analgesics
Panel findings and recommendations:
Literature Reviewed.
No RCTs were found that compared opioid
analgesics (either alone or in combination with other drugs) to a placebo.
Therefore, three studies were evaluated that compared opioid analgesics to
other medications,
[115] -
[117]
recognizing that results of the evaluation would not entirely answer the
question of whether opioids are any better than placebo for back symptoms.
Another article
[118]
contained information used by the panel. Evidence on Efficacy.
All three studies evaluated patients with acute low back
problems, but with a mixed group of medications. Two reports compared
acetaminophen with codeine to diflunisal (an NSAID) with patients treated for
1 and 2 weeks, respectively.
[115],
[116] The
third study compared three groups, one group receiving codeine, one oxycodone
plus aspirin, and one acetaminophen.
[117]
At the conclusion of treatment, Muncie, King, and DeForge
[116] and Brown, Bodison, Dixon, et al.
[115]
found no significant differences between groups in terms of pain relief or
functional improvement.
Wiesel, Cuckler, Deluca, et al.,
[117] who
evaluated a population of military recruits with acute low back pain, found no
difference between the three medication groups in amount of time before
patients returned to full activities. Pain relief was claimed to be superior in
groups receiving opioid analgesics compared with acetaminophen, with the
greatest effect seen in the first 3 days of treatment. No statistics were
reported to support the claim. Potential Harms and Costs.
Side effects reported by subjects receiving acetaminophen with codeine
included dizziness, fatigue, inability to concentrate, impaired vision,
drowsiness, nausea, and constipation.
[115],
[116] In
one study, 35 percent of subjects receiving acetaminophen with codeine had to
discontinue the medication because of intolerable side effects.
[116] Prolonged use of opioid analgesics is associated with the development
of tolerance and physical dependence. A risk of developing physical dependence
with short-term use of opioids has also been reported.
[118]
The expense of treatment with these medications varies greatly,
depending on the medication used and the length of treatment. Summary of Findings.
There are no well-designed controlled
studies that evaluate the use of opioid analgesics compared with no treatment
in patients with acute low back problems. The studies reviewed found that
patients taking opioid analgesics did not return to full activity sooner than
patients taking NSAIDs or acetaminophen. In addition, two studies found no
difference in pain relief between NSAIDs and opioids. Finally, side effects of
opioid analgesics were found to be substantial, including the risk for
physical dependence. These side effects are an important concern in conditions
that can become chronic, such as low back problems. Oral Steroids
Panel findings and
recommendations:
Literature Reviewed.
Of six
articles screened for this topic, the only one meeting criteria for review was
Haimovic and Beresford.
[119] Two
other articles also contained information used by the panel.
[120], [121] Evidence on Efficacy.
Haimovic and
Beresford, [119] in a double-blind RCT, evaluated patients with low back pain who had
findings of a single nerve root irritation (symptom duration of patients not
specified). Patients were randomly assigned to receive a 1-week course of
either an oral dexamethasone or a placebo. On followup at the end of treatment
and at 1 year, no significant differences were found between the two groups in
terms of pain relief. Potential Harms and Costs.
The incidence of side effects associated with steroids correlates with the
potency of the drug, dosage, and duration of administration. Well-recognized
complications from the prolonged use of oral steroids include suppression of
pituitary-adrenal function, fluid and electrolyte disturbance,
hyperglycemia, demineralization of bone, and immunosuppression (with increased
susceptibility to infection). While many of these effects can be reduced or
eliminated with alternate-day therapy, even short-term daily use of high-dose
steroids can contribute to posterior subcapsular cataract formation, myopathy,
central nervous system disturbance, and avascular necrosis of bone, especially
of the femoral head.
[120],
[121]
The expense of treatment varies greatly, depending on the medication used
and the length of treatment. Summary of Findings.
The limited available research evidence indicates that oral steroids do
not appear to be an effective treatment for patients with acute low back
problems. Serious potential complications are associated with long-term use,
but potential complications appear minimal with short-term use. Colchicine
Panel
findings and recommendations:
Literature Reviewed.
Of 13 articles
screened, 3 RCTs met criteria for review.
[122]- [124] Schnebel and Simmons
[123]
evaluated only patients with acute low back problems of less than 3 months'
duration. Meek, Giudice, McFadden, et al.
[122]
evaluated patients with symptoms of more than 2 months. Simmons, Harris,
Koulisis, et al.
[124]
evaluated those with symptoms lasting up to 6 months. Evidence on Efficacy.
Schnebel and Simmons
[123]
found no statistically significant difference between oral colchicine and a
placebo, although the oral colchicine group did have significantly more
diarrhea and vomiting than the placebo group. Simmons, Harris, Koulisis, et
al., [124] who compared groups receiving either intravenous colchicine or intravenous
saline, found significantly improved pain ratings for the colchicine group,
but pain relief was short-lived (lasting from 1 hour to 2 days). Also, two
patients in the colchicine group developed complications (diarrhea and a local
inflammatory response). Meek, Giudice, McFadden, et al.,
[122] who
evaluated for 1 month a group receiving one dose of intravenous colchicine
followed by oral colchicine, compared with a group receiving placebo, found
significantly greater pain relief in the colchicine group. Potential Harms and Costs.
Potential complications from the use of
colchicine are gastrointestinal irritation, skin problems, severe chemical
cellulitis from intravenous infiltration, and bone marrow suppression with
agranulocytosis.
[124] The expense of treatment with colchicine varies greatly, depending on
whether oral or intravenous administration is used and on length of
treatment. Summary of Findings.
Research
evidence is limited and conflicting on whether colchicine, given either orally
or intravenously, is an effective treatment for patients with acute low back
problems. Serious potential side effects have been reported with use of this
medication. Antidepressant Medications
Panel findings and recommendations:
Literature Reviewed.
Of 18 articles screened, 3 RCTs met
review criteria.
[125]- [127] Other articles also contained information used by the panel.
[128], [129] Evidence on Efficacy.
No studies were
found evaluating the efficacy of antidepressant medications for treatment of
acute low back problems. The three studies reviewed all compared an
antidepressant medication to a placebo in a double-blind fashion in patients
with chronic, not acute, low back pain. These studies all randomized patients
to receive either a pharmacologically inert placebo or an antidepressant
medication. Alcoff, Jones, Rust, et al.
[125] used
imipramine, as did Jenkins, Ebbutt, and Evans.
[127] Goodkin, Gullion, and Agras
[126] used
trazodone. The studies found no significant differences between groups
receiving antidepressant and placebo in terms of pain reduction, functional
limitations, depression, or the use of opioids. All three studies had
methodological flaws, including small sample sizes, lack of power
calculations, and incomplete description of followup. Potential Harms and Costs.
Antidepressant medications can produce a
variety of side effects including dry mouth, drowsiness, constipation, urinary
retention, orthostatic hypotension, and mania.
[128],
[129]
The cost of treatment with antidepressant medications can vary from low to
high depending on the medication used, dose, and length of treatment. Summary of Findings.
No studies were found that
evaluated the efficacy of antidepressant medications for treatment of acute
low back problems. The studies reviewed all evaluated patients with chronic low
back problems. They found no significant differences between antidepressants
and placebo on any outcome measured. Numerous reported side effects are
associated with antidepressant medications, but the potential for serious side
effects is small in otherwise healthy adults. Symptom Control: Physical Treatments
Spinal Manipulation
Panel findings and
recommendations:
Literature Reviewed.
Of the 112 articles screened for this topic, 13 reporting on 12 RCTs met
criteria for review.
[72],
[85],
[130] -
[140]
The panel also considered recent meta-analyses and cost analyses.
[141]- [144] In addition, the panel used information from articles that did not
meet selection criteria.
[145]-
[149] Evidence on Efficacy.
The meta-analysis by Shekelle,
Adams, Chassin, et al.
[144] was based on 29 controlled trials of manipulation for low back
problems. Nine of the studies used in the meta-analysis focused on patients
with acute low back problems and tested the effect of manipulation against
sham manipulation
[136] or
various other conservative treatments.
[72], [132], [135], [137], [138], [140], [145], [149]
Of those RCTs that evaluated manipulation in patients with
acute low back pain, the two highest quality studies used similar research
designs.
[136], [137] Both these studies randomly assigned patients to either a group
receiving manipulation or a nontreatment control group, with patients
stratified by whether symptoms had lasted less than 14 days, 14 to 28 days, or
over 28 days in one study.
[137] For
patients with 14 to 28 days of symptoms, both studies found the manipulation
groups had statistically significant improvement in pain relief and
functioning compared with the control groups. However, this effect was only
seen within the first 2 weeks after starting treatment. For patients with
symptoms of less than 14 days or over 28 days, no differences in improvement
were found between the manipulation and control groups for any followup
times.
A meta-analysis of the remaining seven studies also showed
statistically significant short-term effects of manipulation in hastening
recovery from low back problems.
[144]
Another meta-analysis, based on 23 randomized controlled trials of
manipulation or mobilization, came to a similar conclusion.[sup141 This
analysis indicated that, in patients with acute low back problems without
radiculopathy, manipulation reduces pain and has positive short-term impact on
daily functioning. Most studies have concentrated upon outcomes assessed within
the first month of care.
The meta-analysis by Shekelle, Adams,
Chassin, et al.
[144] analyzed, in addition, studies of spinal manipulation in patient
groups who had predominantly chronic low back problems, a mix of acute and
chronic low back problems, or pain of undetermined duration. Studies of
manipulation in these groups had conflicting results concerning the efficacy
of manipulation.
Shekelle, Adams, Chassin, et al.
[144] also
analyzed three studies on the use of spinal manipulation for patients with low
back problems who had radiculopathy, but concluded that the evidence was
insufficient to demonstrate efficacy.
[131],
[146],
[148] Potential Harms and Costs.
Shekelle, Adams, Chassin,
et al. [144] described published case reports of patients presenting with sciatica who
had increasing neurologic deterioration following manipulation, but estimated
that the risk of serious complications from lumbar spinal manipulation is
small and may vary with the clinical condition with which the patient
presents. No systematic report of frequency of complications from spinal
manipulative therapy has been published. Mandell, Lipton, Bernstein, et al.
[147]
listed autonomic disturbances such as faintness, perspiration, and
hyperventilation as common short- term reactions to manipulation. The total
cost of manipulative therapy is determined by the frequency and duration of
care. Summary of Findings.
The evidence for
effectiveness of manipulation varies depending on the duration and nature of
the patient's presenting symptoms. For patients with acute low back symptoms
without radiculopathy, the scientific evidence suggests spinal manipulation is
effective in reducing pain and perhaps speeding recovery within the first
month of symptoms. For patients whose low back problems persist beyond 1 month,
the scientific evidence on effectiveness of manipulation was found to be
inconclusive. For patients with radiculopathy, the scientific evidence was also
inconclusive about either the effectiveness or the potential harms of
manipulation. Finally, the panel offered the opinion that, for patients with
acute low back problems and findings of possible progressive or severe
neurologic deficits, assessment to rule out serious neurologic conditions is
indicated before initiating manipulation therapy. Physical Agents and Modalities
Panel
findings and recommendations:
Literature Reviewed.
Of 25 articles screened for this topic, 10 reporting on 8 RCTs met
criteria for review.
[85],
[133],
[140],
[150] -
[156] Evidence on Efficacy.
Many studies compared
different combinations of physical agents and modalities, making it difficult
to evaluate effectiveness of specific modalities. Only two studies evaluated
physical agents and modalities in patients with acute low back pain.
[85],
[140]
Neither found significant differences in self-rated pain relief or other
outcome measures between patient groups receiving physical agents and
modalities (including diathermy, ultrasound, flexion/extension exercises,
massage, and electrotherapy) and groups receiving a placebo.
The other
studies reported on groups of either chronic or a mix of acute and chronic low
back pain patients. Three studies found no significant differences in
patient-reported outcome measures between treatments (including cutaneous
laser, diathermy, electrotherapy, exercise, heat, massage, and ultrasound) and
a placebo. [133], [150] - [153] Manniche, Hesselsoe, Bentzen, et al.
[155]
found intensive back-strengthening exercises superior to physical agents and
modalities on patient-rated outcome measures, but the group receiving physical
agents/modality treatment was not compared with a control group receiving no
intervention. Melzack, Vetere, and Finch
[156]
found that a group receiving TENS therapy had greater pain relief than a group
receiving massage therapy. Again, treatments were not compared with a
no-intervention control. Linton, Bradley, Jensen, et al.
[154]
found that a group given a combination of physical agents and modalities,
ergonomic education, and behavioral therapy had significantly better outcomes
than a control group receiving no intervention, but the effect of physical
agents and modalities could not be determined. Potential Harms and Costs.
Risks from potential complications of physical agents
and modalities are believed to be small. A possible exception is in pregnant
patients, for whom ultrasound and diathermy are not recommended because of
theoretical risks to the fetus.
The costs of individual treatment
sessions using physical agents and modalities are variable, determined by the
number of modalities used, the length of treatment, and the number of
treatment visits. Summary of Findings.
No
well-designed controlled trials support the use of physical agents and
modalities as treatments for acute low back problems. However, some patients
with acute low back problems appear to have temporary symptomatic relief with
physical agents and modalities. Therefore, self-administered home programs for
modalities involving heat or cold are considered a treatment option. Transcutaneous Electrical Nerve Stimulation
Panel findings and recommendations:
Literature Reviewed.
Of 34 articles screened for
this topic, 9 articles reporting on 8 RCTs met criteria for review.
[156]-
[164]
Only one study evaluated patients with acute low back pain.
[160] Evidence on Efficacy.
Hackett, Seddon,
and Kaminski [160] evaluated a treatment called "electroacupuncture," which consisted of
low-amplitude pulsed electrical current administered by way of surface
electrodes rather than by needles. The panel considered this a variation of
TENS rather than a type of acupuncture since no needling was involved. For the
study, 37 patients with low back pain of less than 3 days' duration were
randomly assigned to groups receiving either two 15-minute treatments of
electroacupuncture and placebo tablets or paracetamol tablets and placebo
electroacupuncture with no current applied. There was no difference in results
at 1 and 2 weeks. By the sixth week after the initial treatment, patients who
had electroacupuncture reported significantly less pain, measured on a visual
analog pain-rating scale, compared with those who took paracetamol.
The other studies reviewed focused on patients with chronic low back pain or
other types of chronic pain or on a mixture of acute and chronic low back pain
patients. The largest randomized study of TENS was carefully blinded and found
no benefit for TENS over sham TENS in patients with chronic low back problems.
[157] The remaining studies were of variable quality and were inconclusive
regarding efficacy of TENS for relieving chronic pain. Potential Harms and Costs.
The risks of TENS are considered low. The
cost of this treatment is considered low to moderate (depending upon whether
the equipment is rented or owned by the patient). Summary of Findings.
There is inconclusive evidence of the efficacy of TENS in
patients with acute low back problems. Only one published study addresses this
issue, and its findings are considered weak. Shoe Insoles and Shoe Lifts
Panel
findings and recommendations:
Shoe lifts (or raises) are additions made to the heel or sole of a shoe to
increase its height. The therapeutic objective of shoe lifts is to compensate
for lower limb length inequality and thereby reduce back pain. Literature Reviewed.
Of seven articles reviewed for this topic, only
one was an RCT that met criteria for review.
[165]
Other articles contained information used by the panel, but did not meet
article selection criteria.
[166]-
[168] Evidence on Efficacy.
Basford and Smith
[165] used
a randomized crossover design to evaluate the use of shoe insoles compared
with no insoles in adults with mild back pain who spent at least 75 percent of
each workday standing. Of 39 subjects studied, 44 percent reported reduced back
pain when using the insoles, 3 percent reported increased back pain, and 51
percent reported no difference. Of the subjects who reported no improvement,
many stated that their shoes were too tight to allow insoles to be added
comfortably.
There were no controlled trials that evaluated shoe lifts
in patients with either acute or chronic low back problems. The extent to
which leg length inequality might be associated with low back problems has not
been established. Lower limb length differences of up to 2 cm are frequently
seen in subjects with no history of low back problems.
[167],
[168] One
study evaluated aircraft industry workers and found no correlation between a
2-cm limb length inequality and either previous back problems or later reports
of back complaints.
[166] Potential Harms and Costs.
Shoe insoles and shoe
lifts are low-risk treatments; their cost varies from low (for ready-made
items) to moderate (for custom-made orthotics). Summary of Findings.
Limited evidence (one crossover study) indicates that shoe
insoles may reduce back pain in some individuals with mild back complaints.
There is no evidence they provide any long-term benefit. The extent to which
leg length inequality might be associated with acute low back problems has not
been established, although differences of less than 2 cm are unlikely to be
problematic. Lumbar Corsets and Back Belts
Panel findings and recommendations:
Literature Reviewed.
Of 31 articles screened, 3 RCTs about lumbar
corsets and support belts met review criteria for adequate evidence about
efficacy.
[131], [169], [170] Another article contained information used by the panel, but did not
meet selection criteria.
[171]
None of these studies evaluated only patients with acute low back problems. One
evaluated only chronic low back pain patients.
[171] One evaluated a mixed group of acute and chronic low back pain
patients. [131] The other two studies evaluated the prevention of low back problems
in workers doing frequent lifting tasks.
[169],
[170] Evidence on Efficacy.
Coxhead, Meade, Inskip, et al.
[131]
compared lumbar corset use to traction, exercise, and manipulation but
included other interventions, making the direct effect of corset use difficult
to determine.
Million, Haavik Nilsen, Jayson, et al.
[171]
compared the use of two types of lumbar corsets, one with and one without a
lumbar support, in patients with chronic low back problems (all with symptoms
longer than 6 months). This study was an RCT, but had too few subjects to meet
review criteria. Although this study found a considerable and significant
improvement in symptoms in the group wearing corsets with a lumbar support, no
control group was used in the study to ascertain the effect of corset use as
compared with no corset use.
Walsh and Schwartz,
[170] in
an RCT, evaluated 90 grocery warehouse workers not currently receiving
treatment for low back problems. Subjects were randomly assigned to three
groups. One group received a custom-molded lumbar corset plus a 1-hour training
program on proper lifting, one the training program alone, and one no
intervention. During the 6-month study period, no significant differences were
reported between groups in back injury rates or in time lost from work due to
back problems. However, the group assigned to lumbar corsets plus training
showed significantly less time loss from work due to back symptoms during the
6 months of the study when compared with the prior 6-month period. No similar
significant effect was found for the other two groups.
Reddell,
Congleton, Huchingson, et al.,
[169] in
an RCT, evaluated 642 airline baggage handlers randomly assigned to use of a
lumbar weightlifting belt, with and without a supplemental training class, or
to the training class alone, or to no intervention. The 1-hour training course
included instruction on proper lifting techniques, and employees were given
stretching exercises to be done before each flight. Over an 8-month period, no
significant differences were found between groups studied in back injury
claims or in days lost from work. However, the validity of these results is
questionable since 58 percent of workers assigned to wear weightlifting belts
stopped using them before the end of the study period. Potential Harms and Costs.
Some authors suggest that the prolonged use
of lumbar corsets and support belts may lead to a decrease in strength of
abdominal and back muscles, but no clear evidence of this was found in
patients with low back problems. Walsh and Schwartz
[170]
found that no such weakness occurred in workers who wore lumbar corsets for 6
months as a preventive measure. In the study by Reddell, Congleton, Huchingson,
et al.,
[169] the majority of workers who stopped wearing weightlifting belts
complained that the belts were too hot and/or too uncomfortable.
The
cost of lumbar corsets and support belts varies from low to moderately
expensive. Summary of Findings.
There is no
evidence that lumbar corsets or support belts are effective for treating acute
low back problems and conflicting evidence on whether lumbar corsets and
support belts are effective for preventing or reducing the impact of low back
problems in subjects who do frequent lifting at work. Traction
Panel findings and
recommendations:
Literature Reviewed.
Of 31 articles
screened for this topic, 7 articles reporting on 6 RCTs met criteria for
review. [131], [138], [139], [172] - [175] Another article contained information used by the panel, but did not
meet selection criteria.
[176] Evidence on Efficacy.
A meta-analysis of the
studies on traction was done by the panel methodologists. Quality rating was
done for the six RCTs reviewed without knowledge of study results. There were
no excellent studies, one good study,
[173] three fair studies,
[131],
[139],
[172] a
fair study reported on by Mathews, Mills, Jenkins, et al.,
[138] and one poor study.
[175]
All the studies involved patients with acute low back pain of less than 3
months' duration, but studies varied on whether patients with a history of
previous low back problems were excluded. Groups receiving traction were
compared with groups receiving sham traction.
[173],
[174]
Traction combined with bed rest and corset use was compared with bed rest and
corset use alone.
[172]
Traction was compared with heat
[138] and
with isometric exercise.
[175] In
addition, Coxhead, Meade, Inskip, et al.
[131] studied groups receiving various combinations of traction,
manipulation, exercise, and corset use in a multifactorial design with 16
cells. The six studies varied with respect to types of traction, control
groups, outcome measures, and assessment periods. For this reason, no attempt
was made to quantitatively combine these data.
Five of the six studies
showed no difference between traction and the comparison group. In one study,
the group treated with bed rest and corset use combined with traction had less
pain at 1 week than those receiving bed rest and corset use without traction,
but this difference was gone by 3 weeks.
[172]
Moreover, some criticize this study because of attention bias against those in
the control group. In general, the studies did not indicate that traction in
any form is beneficial in terms of pain relief, physiological status, length
of hospital stay, functional outcome, or perception of overall improvement for
patients with acute low back problems. The studies were too small to determine
if traction actually harms patients with acute low back problems. Potential Harms and Costs.
The potential harms from traction
relate to debilitation due to prolonged bed rest, including loss of muscle
tone, bone demineralization, and the risk of thrombophlebitis. There is added
risk of increased intraocular pressure and blood pressure with inverted
hanging traction.
[176] The
cost of traction is considered low to moderate if it is done on an outpatient
basis, or high if the patient is hospitalized for traction. Summary of Findings.
Evidence does not demonstrate traction to be
effective in the treatment of patients with acute low back problems. Biofeedback
Panel findings and recommendations:
Literature Reviewed.
Of 13 articles
screened for this topic, 4 reporting on 5 RCTs met criteria for review.
[177]-
[180]
Other studies did not meet panel review criteria because they had fewer than
10 subjects per treatment group, but were used in a meta-analysis.
[181], [182] All of the studies involved patients with chronic low back pain. In
most subjects, pain had persisted for several years. Evidence on Efficacy.
Because these trials presented conflicting
results, a meta-analysis was begun by the panel methodologists. Studies were
assessed for quality without knowledge of the results. There were no excellent
studies, one good study,
[178] three fair studies,
[177],
[180],
[182] and
a fair study reported by Flor, Haag, Turk, et al.
[179] and by Flor, Haag, and Turk.
[181]
There were no poor studies.
The studies involved comparisons of
biofeedback with sham biofeedback;
[178], [179], [181] biofeedback combined with another treatment in comparison with the
other treatment alone;
[177] and
biofeedback alone compared with some other treatment.
[179], [181], [182]
The study with a good quality rating showed no benefit for
biofeedback over sham biofeedback.
[178] Two
studies reported patients in the biofeedback groups developed significantly
better control of paraspinous muscle electromyographic activity.
[178], [180] In neither study did this reduce pain. Thus, of the five studies,
two showed no benefit for biofeedback.
[178], [180] Two showed a benefit for biofeedback: Asfour, Khalil, Waly, et al.
[177] and the study reported by Flor, Haag, Turk, et al.,
[179] and by Flor, Haag, and Turk.
[181] One
study showed a slight benefit for biofeedback compared with a placebo
condition, but reported an even better benefit for relaxation training.
[182] Statistical combination of results from these studies was not done
because it would require requesting the original data from the authors.
Conclusions from the attempted meta-analysis were that biofeedback as a
treatment for low back problems has been studied only for chronic problems,
and that most of the studies are of mediocre quality and arrive at conflicting
results. Potential Harms and Costs.
The risks
for biofeedback are considered low. The costs of biofeedback treatment are
determined by the number of treatment visits. Summary of Findings.
There is conflicting evidence on the effectiveness of
biofeedback for treating patients with chronic low back problems. However,
this technique has not been studied in patients with acute low back problems. Symptom Control: Injection Therapy
Trigger Point and Ligamentous Injections
Panel findings and recommendations:
Literature Reviewed.
Of 14 articles screened for the topics of trigger point and
ligamentous injections, 6 RCTs met criteria for review. Three of these
evaluated trigger point injections into muscle.
[183]- [185] Three evaluated injections into ligamentous structures in the back.
[186]-
[188]
Other articles contained information used by the panel, but did not meet
article selection criteria.
[189]-
[190] Evidence on Efficacy.
Of the articles evaluating
trigger point injections, only Frost, Jessen, and Siggaard-Andersen
[184]
evaluated patients with acute low back problems. The study population, however,
included patients with acute neck or shoulder pain, and data were not given
separately for the patients with low back problems. For the other two RCTs on
trigger point injections, either the patients evaluated had chronic low back
problems [183] or the duration of symptoms was not reported.
[185]
Various medications were used for trigger point injections.
Frost, Jessen, and Siggaard-Andersen
[184] had
two groups receiving either local anesthetic or saline. Bourne
[183] had
three groups receiving methylprednisolone and lignocaine, or triamcinolone and
lignocaine, or lignocaine alone. Garvey, Marks, and Wiesel
[185] had
four groups receiving lidocaine alone, or lidocaine combined with a steroid,
or needle acupuncture (with no injection of material), or vapocoolant spray to
the skin followed by acupressure (using a plastic needle guard). Two studies
included control groups who had no medication injected into muscles,
[184],
[185] but
none of the three studies included a group with no intervention.
Frost,
Jessen, and Siggaard-Andersen
[184] and
Garvey, Marks, and Wiesel
[185]
found no differences between groups in pain relief or other outcome measures
on followup at 1 and 2 weeks posttreatment, respectively. Bourne[183] found
significantly greater pain relief at 3 months followup for the two groups
receiving steroid injections than for the group receiving injections of local
anesthetic alone.
Of the three articles evaluating injections into
ligamentous structures, two studies evaluated patient groups including some
patients with acute low back problems.
[186],
[188] One
study evaluated a subgroup of patients with acute low back problems, all with
pain over the medial iliac crest.
[186] In
the other study, patients were only described as having low back problems for
greater than 1 month's duration without specifying how many patients had
either acute or chronic symptoms.
[188] The
third article evaluating ligamentous injections evaluated only patients with
chronic low back problems.
[187]
Various substances were injected into different ligamentous structures of
the low back. Collée, Dijkmans, Vandenbroucke, et al.
[186]
studied groups receiving injections of either local anesthetic or saline into
an area of tenderness over the medial iliac crest (not specified if into
muscle or ligamentous attachments). Ongley, Klein, Dorman, et al.
[187]
evaluated groups receiving injections of either a dilute phenol solution
(sclerosing agent) or saline into the lumbar interspinal ligament. Sonne,
Christensen, Hansen, et al.
[188]
evaluated groups receiving injections of either a combination of local
anesthetic and steroid or saline alone into the iliolumbar ligament.
Collée, Dijkmans, Vandenbroucke, et al.
[186]
found that for patients with acute low back pain, there was no significant
difference in pain relief between the saline or anesthetic groups, either
immediately postinjection or at 1 or 2 weeks followup. Ongley, Klein, Dorman,
et al. [187] found greater improvement in pain and disability scores for the patients
receiving phenol injections (intended to induce scar) as compared with
saline. Sonne, Christensen, Hansen, et al.
[188]
found that the group receiving injections with a combination of steroid and
local anesthetic had significantly greater improvement in symptoms at 2 weeks
followup than did the group receiving injections with saline. Potential Harms and Costs.
The potential risks of trigger point
injections include damage to nerves or other tissues, infection, and
hemorrhage.
[190] The cost for this treatment is considered low to moderate. Summary of Findings.
Based on limited research
evidence in studies that included patients with chronic problems, the efficacy
of trigger point or ligamentous injections for treating acute low back
problems appears equivocal. The injections can expose patients to serious
potential complications. Facet Joint Injections
Panel findings and recommendations:
Literature Reviewed.
Of 17 articles screened for this
topic, 5 RCTs met review criteria.
[191]-
[195]
Other articles contained information used by the panel, but did not meet
criteria. [196], [197] Evidence on Efficacy.
No articles were
found evaluating patient groups who had only acute low back problems of less
than 3 months' duration. One study evaluated a mixed group of acute and chronic
patients with pretreatment symptom durations ranging from 1 to 12 months.
[191]
Three articles evaluated patients with low back pain of over 3 months'
duration. [192] - [194] One study did not specify symptom duration before treatment.
[195]
Injections were made either into facet joints or into
pericapsular areas around facet joints. The latter type of injection was also
referred to as a "facet nerve block" when a local anesthetic was used.
Medications injected included steroids, local anesthetics, and saline (either
alone or in combination).
Three studies evaluated a combination of
steroid and local anesthetic injected into either facet joints or pericapsular
areas.
[193]- [195] Three studies evaluated groups receiving facet joint injections in
which steroid was compared with saline,
[192] or
local anesthetic was compared with saline,
[191] or a combination of steroid and local anesthetic was compared with
saline. [193]
None of the five studies that met review criteria found any
significant differences between groups for patient-rated pain relief or global
improvement scores during followup periods of up to 3 months after treatment.
The only study with followup beyond 3 months found significantly greater
improvement in pain and functional disability ratings at 6 months followup for
the group receiving steroid facet injections compared with saline facet
injections, but no significant differences between groups in number of
patients who had sustained improvement over the entire 6-month followup
period. [192] Potential Harms and Costs.
Some of the
articles reviewed noted transient local pain at the injection sites. The risks
of facet joint injections include potential infection, hemorrhage, neurologic
damage, and chemical meningitis,
[196],
[197] as
well as x-ray exposure from fluoroscopy. Facet injections are considered a
moderate- to high-cost treatment. Summary of Findings.
No studies have adequately investigated the efficacy of facet
injections for patients with acute low back problems. However, there were an
adequate number of studies evaluating facet injections for chronic low back
problems. [192]- [195] One study evaluated a mix of acute and chronic problems.
[191] Neither the type of agent injected (steroid, local anesthetic,
saline, or a combination of these) nor the location of the injection
(intrafacet or pericapsular) made a significant difference in patient outcomes
during the first 3 months after treatment or in the percentage of patients
with sustained improvement over 6 months.
Based on limited research
evidence, facet joint injections appear to be associated with rare potential
serious complications and do not appear to be effective for treating acute low
back problems. Epidural Injections (Steroids, Lidocaine, Opioids)
Panel findings
and recommendations:
There are various techniques for performing
the epidural injection, some of which are more precise than others.
[198]
According to White,
[199]
placement of epidural needles is incorrect in 25 percent of the cases. Literature Reviewed.
Of 74 articles screened for this topic,
9 RCTs met criteria for review.
[138],
[200] -
[207]
Other articles contained information used by the panel, but did not meet
article selection criteria.
[147],
[198],
[199],
[208],
[209] Evidence on Efficacy.
Two studies evaluated patients
with acute low back pain of less than 3 months' duration and also with
radicular symptoms and findings suggesting nerve root dysfunction.
[138],
[202]
Both studies compared groups receiving epidural injections of steroids
combined with local anesthetic to groups receiving injections of local
anesthetic alone, either into the epidural space
[202] or
into a tender spot over the sacrum.
[138]
Cuckler, Bernini, Wiesel, et al.
[202]
found no significant differences in pain relief between groups immediately
posttreatment or at long-term followup (mean of 20 months). Mathews, Mills,
Jenkins, et al.
[138]
found no significant differences in pain relief between groups at 1, 6, or 12
months followup, but the epidural steroid group did have significantly better
results at 3 months followup.
The remaining seven studies evaluated
groups with either chronic low back problems or a mix of acute and chronic
problems. [200], [201], [203] - [207] Medications used and locations injected varied. Four studies
evaluated groups receiving epidural injections with various combinations of
steroids, local anesthetics, and/or saline.
[200], [201], [205], [207] Two studies evaluated groups receiving either epidural steroid
injections or injections of saline into the interspinous ligament.
[204], [206] One study evaluated groups receiving epidural injections with
various combinations of steroids and morphine.
[203]
The five studies that reported on short-term pain relief at 2 to 4 weeks
followup showed conflicting results. For this time period, three studies
reported significantly greater pain relief for the epidural steroid groups.
[201],
[204],
[206] The
other two studies found no differences in pain relief between groups.
[205],
[207]
Five studies reported on followup beyond 1 month.
[200], [201], [204], [205], [207] Only one found significantly greater pain relief for the epidural
steroid group.
[200] The
other studies found no significant differences in pain relief between groups.
One study did find that a significantly higher percentage of the group
receiving epidural steroid injections had returned to work at 3 months.
[204] Three studies showed significantly better results within the first
month for epidural steroids versus local anesthetic or saline injections, but
not on longer followup.
[201],
[204],
[206] No
significant differences were reported between groups at 3 months
[204] or
at 1 year. [201] Ridley, Kingsley, Gibson, et al.
[206] did
not report followup beyond 2 weeks. Two other studies found no significant
differences in pain relief between groups for any followup period.
[205],
[207] One
study that evaluated epidural injections of morphine compared with (and/or in
combination with) steroids found no significant differences in pain relief
between groups on either short-term (within 1 month) or longer term followup.
[203] Potential Harms and Costs.
Reported complications of
epidural injections are described by Kepes and Duncalf.
[208] The
primary major complication reported was rare epidural abscess. Minor transient
complications included headache, fever, and inadvertent spinal tap. Rocco,
Frank, Kaul, et al.
[209]
reported several cases of life-threatening ventilatory depression in patients
who received epidural injections of morphine and steroids combined. In 5 of
the 19 times such injections were given, the patients experienced respiratory
depression to the point of somnolence and had to receive naloxone for reversal
of narcosis. Also posttreatment, the respiratory rates of patients receiving
epidural morphine were lower than for patients receiving epidural steroids
alone. The lowest respiratory rates were seen in those receiving injections of
morphine combined with steroids. Mandell, Lipton, Bernstein, et al.
[147]
described headache as the most common side effect of epidural steroid
injections (presumably resulting from pressure changes in the epidural space
or accidental puncture of the dura) and listed aseptic meningitis, infection,
and neurologic problems as other possible complications. Epidural injections
are considered an expensive treatment. Summary of Findings.
Limited research evidence indicates that epidural injections
using any type of medication lack proven efficacy for treating patients with
acute low back pain without radiculopathy. Epidural injections are invasive
and pose rare but serious potential risks. There was no evidence that epidural
steroids are effective in treating acute radiculopathy, but the panel's
opinion was that epidural steroid injections may be useful as an attempt to
avoid surgery. Acupuncture
Panel findings and recommendations:
Literature Reviewed.
Of 24 articles
screened for this topic, 8 reporting on 6 RCTs met criteria for review.
[161],
[162],
[210] -
[215] The
panel also examined a meta-analysis.
[216]
Other articles contained information used by the panel, but did not meet
article selection criteria.
[217]-
[220] Evidence on Efficacy.
All six RCTs evaluated
patients with chronic back problems (with or without leg symptoms) of greater
than 6 months' duration. Four of the articles reporting on three RCTs compared
groups that received needling with groups that received no needling.
[161],
[162],
[210],
[213]
Needling received was either acupuncture in traditional Chinese meridians
[161],
[162],
[210] or
needle insertion into tender muscle points.
[213] In these studies, the groups that received some type of needling
intervention had significantly better outcomes (in pain reduction and
increased activity levels) than did the groups receiving no needling.
The remaining four articles reporting on three RCTs compared groups receiving
acupuncture in the traditional Chinese meridians to groups receiving various
types of needle insertion in other parts of the back.
[211]- [215] None of these studies found any significant differences between
groups in any outcomes measured.
A meta-analysis, based on 51 clinical
studies on acupuncture used for various types of chronic pain (including back
pain), found that the quality of even the better studies was mediocre and
their results highly contradictory.
[216] Specifically noted was that most of these studies did not provide an
appropriate control group or were not adequately blinded. None of the studies
demonstrated an advantage of needling in the appropriate Chinese meridians
over misplaced needling. In this meta-analysis, the authors concluded that the
efficacy of acupuncture for treatment of chronic pain remains doubtful. Potential Harms and Costs.
Reported complications of
acupuncture include hematomas, infections (hepatitis B and Staphylococcus
aureus), pneumothorax, and spinal nerve and spinal cord injuries due to buried
needles migrating to the spinal cord.
[217]- [220] In addition, the panel offered the opinion that needle insertion
treatments involve some discomfort. Costs of acupuncture and other dry
needling treatments vary depending on the number of treatment visits. Summary of Findings.
No studies were found evaluating
efficacy of acupuncture in patients with acute low back problems. In three of
the six RCTs evaluating efficacy for chronic low back problems, outcomes were
better for the acupuncture group than for nontreatment control groups. All
studies had methodologic flaws. Acupuncture was also found to have risks of
significant complications. Activity Modification
Activity Recommendations
Panel findings and
recommendations:
Literature Reviewed.
Evidence on Efficacy.
Other biomechanical research suggests that certain postures and activities
increase the mechanical stress on the spine.
[221],
[223],
[225] It
is not clear whether these mechanical stresses are the cause of low back
problems. However, once symptoms are present, mechanical stresses correlate
with worsening of symptoms. Prolonged sitting and postures that involve
bending and twisting have been shown to increase the mechanical stress on the
spine according to pressure measurements in lumbar intervertebral discs. Heavy
lifting also appears to increase mechanical stress on the spine, but this
stress can be reduced if the lifted object is held close to the body rather
than at arm's length.
A lifting equation to calculate appropriate
lifting limits for various tasks was part of a guideline developed in 1981 by
the National Institute of Occupational Safety and Health
[227] and
revised more recently.
[228]
Unfortunately, the ability of the guideline to reduce the incidence of low
back problems has yet to be directly validated. Other ergonomic guidelines for
safe lifting have been reviewed by Dul and Hildebrandt.
[224] Summary of Findings.
In recommending
activity modifications for patients who work, the clinician may find it
helpful to obtain from the employer a description of the physical demands of
required job tasks. The nature and duration of limitations will depend on the
clinical status of the patient and the physical requirements of the job.
Activity modifications must be time-limited, clear to both patient and
employer, and reviewed by the clinician on a regular basis.
Several
ergonomic guidelines on lifting and materials-handling tasks are available to
help the clinician provide ranges of activity alterations at work. These
guidelines are based on various biomechanical assumptions and theoretical
equations to build a margin of safety for individuals who have to lift at
work. It should be remembered that such guidelines were developed or otherwise
healthy workers and are therefore of limited use in making strict
recommendations. None of these guidelines has been adequately tested to see if
adherence will reduce the occurrence of low back problems.
The panel
recommends that clinicians help patients establish activity goals, in
consultation with their employer when applicable. Such goals are particularly
important for the small percentage of patients who are still not able to
overcome activity intolerance after 1 to 2 months of symptoms. Since
nonphysical factors, such as emotional distress or low work satisfaction, may
also affect an individual's symptoms and response to treatment, activity goals
can help keep attention focused on the expected return to full functional
status and emphasize physical conditioning to improve activity tolerance. Bed Rest
Panel
findings and recommendations:
Literature Reviewed.
Evidence on Efficacy.
One problem with these
studies is that the actual amount of bed rest reported by the subjects often
differed greatly from the amount recommended. Deyo, Diehl, and Rosenthal
[229]
found that 74 percent of the 99 subjects assigned to the 7-day bed rest group
reported fewer than 7 days of actual bed rest. The study reported by Evans,
Gilbert, Taylor, et al.
[75] and Gilbert, Taylor, Hildebrand, et al.
[230]
found that subjects who did not receive a bed rest recommendation also
reported trying bed rest, but the duration was less than for the group
receiving the recommendation. Potential Harms and Costs.
Summary of Findings.
Exercise
Panel recommendations and
findings:
Literature Reviewed.
Other articles contained information used by the panel, but did not meet
article selection criteria.
[221],
[226],
[232],
[244] -
[253]
Only six of the articles reviewed involved studies of exercise as a
treatment for patients with acute low back problems.
[75],
[83],
[86],
[131],
[234],
[243]
Two other studies evaluated the efficacy of exercises for preventing or
reducing the impact of low back problems in workers whose jobs involved
frequent lifting.
[236],
[237] The
remaining articles all evaluated exercise as a treatment for groups that
contained only patients with chronic pain or a mix of patients with acute and
chronic problems. These were given less weight by the panel as there were
enough studies using patients with acute low back problems. Evidence on Efficacy.
The other five articles dealing with acute low back problems
included interventions that made the effect of exercise difficult to
determine.
[75], [86], [131], [234], [243]
Stankovic and Johnell
[86]
compared McKenzie extension exercises to a 45-minute educational session and
found that the exercise group stopped medication use earlier and reported more
pain relief and fewer days off work. Evans, Gilbert, Taylor, et al.
[75] found
that patients who received a flexion exercise program plus a 30-minute
educational program stopped using medication sooner than did patients in bed
rest and control groups. However, no differences were found between groups in
reported degree of pain relief or activities of daily living.
The
other three of these five studies showed no significant differences in
outcomes between the treatment groups.
[131],
[234],
[243]
Davies, Gibson, and Tester
[234]
compared groups receiving short-term diathermy and either extension or flexion
exercises. Zylbergold and Piper
[243]
compared flexion exercises to manual therapy in combination with home back
care instructions. Coxhead, Meade, Inskip, et al.
[131]
compared groups receiving various combinations of exercise (not otherwise
specified), traction, manipulation, and lumbar corset use in a multifactorial
study with 16 cells.
In summary, the six studies, which evaluated
exercise for treating acute low back problems, used different forms of flexion
or extension exercises, different treatment or control groups, different
outcome measures, and different assessment periods. For this reason, no
attempt was made to quantitatively combine these data.
As noted
previously, two studies evaluated exercise for preventing acute or recurrent
episodes of low back problems. Gundewall, Liljeqvist, and Hansson,
[236] in a
RCT, evaluated 60 nursing personnel working at a geriatric hospital. Subjects
were randomized to receive either no intervention or a supervised exercise
program during work six times per month for 13 months (emphasizing isometric
and dynamic exercises strengthening the back extensor muscles).
At the
end of the study, the exercise group had a significantly lower incidence of
new low back problem episodes when compared with the control group (4 percent
compared with 38 percent), fewer days lost from work, fewer days with back
pain complaints, and a lower average duration of low back pain complaints.
Trunk extensor strength measured with a spring gauge was not different between
groups at the start of the study, but at the end of the study average trunk
strength was significantly greater in the exercise group compared with the
control group. The authors noted that the exercise group did receive more
attention than the control group, which could account for some of the positive
effect. Results were not reported separately for those with and without prior
low back problems.
In the second study, Kellett, Kellett, and
Nordholm,
[237] in a RCT, evaluated 60 workers at a kitchen cabinet manufacturing
company in Sweden. All were working at the start of the study and reported
having either current or prior back pain. Subjects were randomly assigned to a
control group or an exercise group. The exercise group was offered an exercise
program at work once per week (30 minutes of aerobic movements of the arms,
legs, and trunk followed by 10 minutes of relaxation) and were asked to do 30
minutes of aerobic exercise (such as walking, jogging, or cycling) on their
own at least once per week.
Although subjects in the exercise group
were encouraged to progressively increase their effort level during exercise,
no direct measures of exertion (such as heart rate) were recorded. The
exercise group was also given lectures about back problems and proper lifting
techniques. There were no significant differences between exercise and control
groups in incidence rates or days lost from work for episodes of back pain in
the 1.5 years before the intervention. The incidence rate and days lost from
work for episodes of back pain decreased in the exercise group during the
subsequent 1.5-year intervention period. In the control group, absenteeism
attributable to back pain increased during the intervention period. There were
no significant differences, either before or after the study, between groups
in cardiovascular fitness as measured by a suboptimal bicycle ergometer.
Deyo [232] remarked that, although there seems to be a consensus among experts that
exercise plays a major role in the treatment of low back symptoms, most
treatment programs prescribe a combination of exercises and there is little
agreement on specific regimens. He also offered an opinion that additional
benefits of aerobic exercise may include weight loss and favorable
psychological effects, such as reduction of anxiety and depression. Other
studies have shown that patients improve faster when given specific quotas of
exercises to do rather than being told to stop exercise when it produces pain.
[83],
[246]
One study [251] found a back-specific exercise machine (the B-
[200]) does not provide added benefit over traditional exercise in
improving the objective back strength and flexibility (as measured by
functional lifting capacity) of low back patients. Potential Harms and Costs.
Many methods have been proposed to evaluate mechanical stress on the
back in different postures and activities.
[221],
[226],
[244],
[245],
[247] -
[250],
[252] A
biomechanical model by Schultz directly correlates with in vivo measurements
of intradiscal pressure and myoelectric signals.
[253] The measurements of relative stress on the spine during postures and
activities generally relate to increased and decreased symptoms experienced by
patients with back problems. Thus, this information can be used for
recommendations about safety and altering activity. The costs of exercise
programs can vary depending upon the setting. Those performed at home are
inexpensive, whereas those done in supervised clinical settings are more
costly. Exercise programs using back-specific computerized exercise machines
can be very expensive. No studies meeting review criteria were found that
provided evidence of any of these exercise settings being more effective than
the others. Summary of Findings.
Exercise programs aimed at improving general endurance
(aerobic fitness) and muscular strength (especially of the back and abdomen)
have been shown in some published studies to benefit patients with acute low
back problems. No evidence supports stretching as effective treatment for acute
low back problems. The panel offered the opinion that patients with acute low
back problems would benefit from exercise programs if endurance programs are
started early, using exercises that cause minimal mechanical stress on the
back; if patients are given set exercise quotas gradually increased with time;
and if later strengthening programs are individualized based on the level of
activity to which patients wish to return. The panel suggested that the early
goal of exercise programs is to prevent debilitation due to inactivity and
then to improve activity tolerance to return patients to their highest level
of functioning as soon as possible.
4. Special Studies and Diagnostic Considerations
After
the first month of symptoms, the vast majority of patients have recovered from
activity limitations due to low back problems. However, if the patient is
limited by back symptoms for more than 1 month, special diagnostic and
treatment procedures are often considered to find a reason for the slow
recovery (Attachment A3). Tests commonly used to identify focal neurologic physiologic
dysfunction include electromyography (EMG), sensory evoked potentials (SEPs),
and thermography. To detect physiologic dysfunction of nonneurologic diseases,
general laboratory screening tests, such as erythrocyte sedimentation rate
(ESR), complete blood count (CBC), and urinalysis (UA), and bone scan have
been proposed. Needle EMG and H-reflex tests of the lower limb may be useful in assessing
questionable nerve root dysfunction in patients with leg symptoms lasting
longer than 4 weeks (regardless of whether patients also have back pain).
(Strength of Evidence = C.) If the diagnosis of radiculopathy is
obvious and specific on clinical examination, electrophysiologic testing is
not recommended. (Strength of Evidence = D.) Surface EMG and F-wave
tests are not recommended for assessing patients with acute low back
symptoms. (Strength of Evidence = C.) SEPs may be useful in assessing
suspected spinal stenosis and spinal cord myelopathy. (Strength of Evidence =
C.) Electrophysiologic tests are sometimes used in
patients with sciatica to evaluate physiologic functioning of the spinal cord,
nerve roots, and peripheral nerves. Overall diagnostic objectives of these
tests are to assess suspected myelopathy (dysfunction of the spinal cord),
radiculopathy (dysfunction of a spinal nerve root), neuropathy (dysfunction of
a peripheral nerve distal to the nerve root), and myopathy (muscle
abnormalities). The tests and their specific diagnostic objectives for low back
problems are as follows:
Needle electromyography (EMG), used to
assess acute and chronic nerve root dysfunction, myelopathy, and myopathy. H-reflex, a test measuring sensory conduction through nerve roots,
used mostly to assess S-
[1]
radiculopathies. F-wave response, a test measuring motor conduction
through nerve roots, used to assess proximal neuropathies. Surface
EMG, used to assess acute and chronic recruitment patterns during static or
dynamic tasks using surface electrodes instead of needle insertion. SEPs, used to assess sensory neurons in peripheral and spinal cord pathways. Nerve conduction studies, used to assess acute and chronic peripheral
entrapment neuropathies that may mimic radiculopathies. Of 52 articles screened for this topic, 8 met
review criteria for adequate evidence about efficacy.
[21],
[254] -
[260] Also
reviewed was one study that evaluated findings in asymptomatic subjects who
had no history of low back problems.
[261]
Other studies contained information used by the panel.
[49], [50], [147] Reference tests used to determine
diagnostic accuracy (true positive and true negative rates) of needle EMG
included surgical findings.
[21], [254], [260] They also included clinical followup (pain rating and work status),
with posttest at 1 year.
[257] The
amount and quality of data that could be used to calculate diagnostic accuracy
of these tests varied significantly between studies. Many studies had major
methodological flaws such as biased test interpretations, faulty cohort
assembly, and poor clinical descriptions. Determining the accuracy of EMG is
difficult as well because anatomic defects seen at surgery, which are used in
many of these studies as the reference standard for EMG, may or may not be the
cause of symptoms. This makes true positive and true negative rate
determinations of questionable value. Inserting small needle electrodes into muscle tissue is invasive, causes some
patients discomfort, and may cause bruising. Patients who have severe pain, low
pain thresholds, excessive anxiety, or conflicting emotional symptoms may not
be able to participate fully in the examination.
[147] EMG and other electrophysiologic tests are moderately expensive. The evidence suggests that in
patients with low back problems who have a confusing clinical picture of
severe leg symptoms of more than 3 to 4 weeks' duration, EMG and H-reflex
tests appear to be useful (1) to document presence or absence of radiculopathy
or neuropathy as the cause of symptoms in the lower extremities, (2) to
provide more information on specific nerve roots that may be compromised, and
(3) to help differentiate between acute and chronic nerve root dysfunction.
Optimal time for needle-EMG testing is after the patient has had lower limb
symptoms at least 3 to 4 weeks. Test results are not reliable before this
time. Bone scanning, a type of radionuclide imaging, involves
intravenous injection of radioactive compounds known to adhere to
metabolically active bone. Gamma detectors localize regions of uptake. Most of
the bone-seeking compounds used contain the radionuclide technetium-
[99]m. The
diagnostic objective is to detect occult fractures, infections, and bony
metastases of the spine and to differentiate them from common benign pathology
such as degenerative changes. Of
26 articles screened for this topic, 5 met criteria for review.
[262]- [266] In the studies
reviewed, bone scan was used to detect several different clinical conditions:
stress fracture injuries of the pars interarticularis;
[263] inflammatory sacroiliitis;
[262],
[264]
spine infections;
[266]
metastatic cancer and other systemic disease;
[265] and symptomatic spondylolysis.
[263] All
of these studies either evaluated mixed patient groups with both acute and
chronic problems or did not report symptom duration.
[264], [265] There were no studies focusing specifically on patients with acute
low back pain. The primary potential complications of bone
scan involve exposure to ionizing radiation from the radionuclide injected.
The total radiation dose to the patient is equivalent to a set of lumbar spine
x-rays. This test is contraindicated during pregnancy. The radionuclide may be
found in breast milk, and breast feeding must be discontinued for a brief
interval after the test. Bone scans are moderately expensive. The bone scan is a moderately sensitive test
for detecting suspected tumor, infection, or occult fractures of the vertebrae
in patients with low back pain, but not for specifying the diagnosis. A
positive bone scan suggesting one of these conditions will usually need to be
confirmed using other diagnostic tests or procedures. Bone scan has been shown
to be moderately sensitive for detecting metastases to the spine in patients
with a previously established diagnosis of cancer who present with acute low
back problems. Bone scan also appears to be effective for detecting serious
conditions, such as tumor, infection, or fracture, in patients where there is
suspicion of these problems based on clinical findings. Bone scan appears to
be more accurate than plain x-ray for detecting these conditions. No studies
were found comparing the relative accuracy of bone scan versus CT scan or
magnetic resonance imaging (MRI) scan for detecting the conditions. In patients with low back problems, thermography
involves measuring small temperature differences between sides of the body and
evaluating the patterns on infrared thermographic images of the back and lower
extremities. Because thermography is noninvasive and involves no ionizing
radiation, the test has been proposed as a physiologic test with clinical
utility for documenting the presence or absence of radiculopathy (nerve root
compression). Of 17 articles
screened for this topic, only 1 met review criteria for adequate evidence
about efficacy.
[267] The
panel also reviewed a meta-analysis on thermography.
[268] Reviewed as well were four articles providing data on thermography in
asymptomatic subjects without back problems.
[269]-
[272] The one study meeting review
criteria [267] evaluated thermography in 107 patients who had sciatica of
unspecified duration, 19 of whom went on to have low back surgery, and 28
asymptomatic subjects with no history of back problems and no evidence of
disease affecting the lower extremities. All the asymptomatic subjects had
temperature differences on thermography of less than 1.9 degreesC in the feet
and less than 1.0 degreesC in other parts of the lower limbs. These values
were used as the upper limits of normal for evaluating patients with
sciatica. Of the 19 patients with sciatica who went on to have surgery, only 53
percent had results on preoperative thermography in agreement with surgical
findings. No reports of
significant risks from thermography were found. Thermography is considered
moderately expensive. The
one study meeting review criteria found that thermography did not accurately
predict either the presence or absence of lumbar nerve root compression found
at surgery. In addition, several studies have shown thermography of the lower
limbs as abnormal in a substantial proportion of asymptomatic subjects without
back problems. Based on the available research evidence, thermography does not
appear effective for diagnosing low back problems. In addition to x-rays, the imaging studies most generally used to
define a possible anatomic cause for evidence of physiologic abnormalities
include plain myelography, MRI, CT, CT-myelography, discography, and
CT-discography. Plain x-rays are not recommended for routine evaluation of patients with acute
low back problems within the first month of symptoms unless a red flag is
noted on clinical examination (such as specified below). (Strength of Evidence
= B.) Plain x-rays of the lumbar spine are recommended for ruling out
fractures in patients with acute low back problems when any of the following
red flags are present: recent significant trauma (any age), recent mild trauma
(patient over age 50), history of prolonged steroid use, osteoporosis, patient
over age 70. (Strength of Evidence = C.) Plain x-rays in combination
with CBC and ESR may be useful for ruling out tumor or infection in patients
with acute low back problems when any of the following red flags are present:
prior cancer or recent infection, fever over 100 degreesF, IV drug abuse,
prolonged steroid use, low back pain worse with rest, unexplained weight
loss. (Strength of Evidence = C.) In the presence of red flags,
especially for tumor or infection, the use of other imaging studies such as
bone scan, CT, or MRI may be clinically indicated even if plain x-rays are
negative. (Strength of Evidence = C.) The routine use of oblique views
on plain lumbar x-rays is not recommended for adults in light of the increased
radiation exposure. (Strength of Evidence = B.) X-ray, or radiography, is the oldest and most widely available modality for
imaging the lumbar spine. The most commonly used x-ray views of the lumbar
spine, the standard anteroposterior and lateral views, permit assessment of
lumbar alignment, comparison of vertebral body and disc space size, assessment
of bone density and architecture, and gross evaluation of soft tissue
structures. Oblique views of the lumbar spine are used in the detection of
unilateral or bilateral spondylolysis. Other special views include sacroiliac
views to evaluate possible ankylosing spondylitis. The diagnostic objective of
x-rays is to reveal the bony and structural abnormalities associated with back
pain. Of the 128 articles screened
for this topic, 20 articles reporting on 18 studies met criteria for review.
[26],
[276] -
[294]
Other articles contained information used by the panel, but did not meet
article selection criteria.
[295],
[296] Two articles evaluated patients
who had less than 3 months of symptoms.
[26],
[278] Two
articles involved patients with chronic low back pain.
[282], [292] Two articles had three separate groups, one asymptomatic, one with
patients seen for acute low back problems, and a third comprising patients
with chronic low back symptoms.
[277],
[281] The
remaining 14 articles (reporting on 13 studies) involved a mix of patients
with acute and chronic symptoms or did not report symptom duration.
[276], [279], [280], [283] - [291], [293], [294] Potential harms associated with lumbar
spine x-rays are primarily related to the degree of ionizing radiation
exposure. Small cumulative doses of ionizing radiation are believed to present
minimal or no risks. But lumbar x-rays expose the male and female reproductive
organs, especially with routine use of oblique views or repeated exposures.
These practices are of questionable value and a particular concern for younger
females. Oblique lumbar views approximately double total radiation exposure,
compared to standard views, which alone are equivalent to female gonadal
radiation of daily chest x-rays for 6, 16, or 96 years, depending upon the
machine.
[296] Lumbar spine x-rays are seldom indicated during pregnancy. Plain lumbar x-rays have been
demonstrated to be useful in helping detect or define spinal fractures, but
alone do not rule in or out tumors or infections suspected by other findings
(such as when red flags are present). Evidence suggests plain x-rays are rarely
useful in evaluating or guiding treatment of adult acute low back pain in the
absence of red flags. Plain x-rays are not effective for diagnosing lumbar
nerve root impingement of herniated disc or spinal stenosis, or for ruling out
cancer or infection. In the presence of red
flags suggesting cauda equina syndrome or progressive major motor weakness,
the prompt use of CT, MRI, myelography, or CT-myelography is recommended.
Because these serious problems may require prompt surgical intervention,
planning for use of such imaging studies is best done in consultation with a
surgeon. (Strength of Evidence = C.) CT, MRI, myelography, or
CT-myelography and/or consultation with an appropriate specialist is
recommended when clinical findings strongly suggesting tumor, infection,
fracture, or other space-occupying lesions of the spine. (Strength of Evidence
= C.) Routine spinal imaging tests are not generally recommended in
the first month of symptoms except in the presence of red flags for serious
conditions. After 1 month of symptoms, an imaging test is acceptable when
surgery is being considered (or to rule out a suspected serious condition).
(Strength of Evidence = B.) For patients with acute low back problems
who have had prior back surgery, MRI with contrast appears to be the imaging
test of choice to distinguish disc herniation from scar tissue associated with
prior surgery. (Strength of Evidence = D.) CT-myelography and
myelography are invasive and have an increased risk of complications. These
test are indicated only in special situations for preoperative planning.
(Strength of Evidence = D.) The following are minimal quality criteria
for imaging studies of the lumbar spine (Strength of Evidence = B):
CT and MRI cuts to be made no wider than 0.5 cm and parallel to the vertebral
endplates. MRI scanners to have a magnetic field strength no less than
0.5 T (tesla) and to allow a scanning time adequate for optimal image
acquisition. Myelography and CT-myelography to use water-based
contrast media. The technical protocols for these imaging tests to be
described on radiologist reports. The four imaging tests commonly used in
assessing the anatomy of the lumbar spinal canal and its contents are plain
myelography, CT scan, MRI scan, and CT-myelography. These four tests are
discussed as a group because they are used in similar clinical situations,
provide similar types of information, and are often compared with each other
in research studies. Evaluation is limited by lack of a gold standard for
evaluating efficacy. Each test and the type of information it provides are
described briefly as follows:
CT scans use multiple x-ray beams
projected at different angles and levels to produce computer-generated axial
cross-sectional images of the body. MRI scans use magnetic fields to
produce computer-generated axial and sagittal cross-sectional images of the
body. Plain myelography uses plain x-rays, taken after a nonionic
water-soluble contrast media is injected into the spinal canal via a lumbar
puncture needle, to produce images of the borders and contents of the dural
sac. CT-myelography uses a CT scan, done after a contrast media has
been injected into the dural sac in the same manner as for plain myelography,
to produce axial cross-sectional images of the spine that enhance distinction
between the dural sac and its surrounding structures. For myelography, contrast media should be water based, not
oil based. For CT scans, the axial images (cuts) should be no wider
than 0.5 cm and should be parallel to the vertebral endplates. For
MRI scans, the image quality should be equivalent to or better than scans with
magnetic field strength >0.5 T with an adequate scanning technique. Because
of significant advances in technology, studies of MRI scans before 1985 were
not considered. Back-related leg symptoms and
clinically specific detectable nerve root compromise with symptoms severe
enough to consider surgical intervention. A history of neurogenic
claudication and other findings suggesting spinal stenosis with symptoms
severe enough to consider surgical intervention. Clinical examination
findings or other test results suggesting other serious conditions affecting
the spine (such as cauda equina syndrome, spinal fracture, infection, tumor,
or other mass lesions or defects). Discography is invasive, and its use is not recommended for assessing patients
with acute low back pain. Interpretation is equivocal, and complications can
be avoided with other noninvasive techniques. (Strength of Evidence = C.) Due to increased potential risks, CT-discography is not recommended over
other imaging studies (MRI, CT) for assessing patients with suspected nerve
root compression due to lumbar disc hernia. (Strength of Evidence = C.) Discography involves the injection of a water-soluble
imaging material directly into the nucleus pulposus of the disc. Information
is then recorded about the amount of dye accepted, the pressure necessary to
inject the material, the configuration of the opaque material, and the
reproduction of the patient's pain. There are two diagnostic objectives: (1) to
evaluate radiographically the extent of disc damage on discogram (sometimes
with the addition of CT) and (2) to characterize the pain response (if any) on
disc injection to see if it compares with the typical pain of the patient. A
symptomatic degenerative disc is considered one that disperses injected
contrast in an abnormal pattern, extending to the outer margins of the annulus
and possibly into epidural space as well. For many investigators, a painful
reaction provoked in the patient that reproduces the patient's usual pain is
required to classify the disc as abnormal. Of the 42 articles evaluated for this topic, only 1 met review
criteria for adequate evidence about efficacy.
[324]
Another article contained information used by the panel, although it did not
meet article selection criteria.
[325]
There were also two articles reviewed that evaluated results of discography in
asymptomatic subjects.
[326],
[327] No studies were found that
evaluated discography for patients with acute low back problems. One of the
major problems in evaluating the literature on discography is that few studies
evaluate discography using an independent reference standard. Instead, many
studies either compare discography results with other diagnostic test findings
or evaluate discography using pain provocation on disc injection as evidence
of discogenic pain, which essentially means using part of a test to validate
itself. Discography is an
invasive procedure with risk of complications. Potential complications include
disc and disc space infections, disc herniation following disc injection, and
significant amounts of ionizing radiation exposure with CT-discography
(estimated at 1.5 to 4.0 rads when studying 2-3 discs).
[325] Discography is expensive. Although discography seeks to identify internal changes in the disc
based on evaluation of a discogram and pain response on disc injection, the
disease process is not clear (the internal disc disruption), and how to use
the information for acute low back problems is not clear. The main reason put
forward for using discography appears to be to determine the levels at which
spinal fusion will be successful in patients with persistent low back problems
(due to discogenic disease). This assumes the controversial premise of a
"painful disc syndrome" which has not yet been adequately documented. Surgery is commonly discussed for back symptoms that are
unresolved after special studies
(Attachment A4). Patients may benefit from general information about the risks and
potential outcomes of surgical treatment for different diagnoses. It is recommended that the treating
clinician discuss further treatment options, with the patient with sciatica
after approximately 1 month of conservative therapy. The clinician should
consider referral to a specialist when all of the following conditions are
met: (1) sciatica is both severe and disabling, (2) symptoms of sciatica
persist without improvement or with progression, and (3) there is clinical
evidence of nerve root compromise. (Strength of Evidence = B.) Standard discectomy and microdiscectomy are of similar efficacy and appropriate
for selected patients with herniated discs and nerve root dysfunction.
(Strength of Evidence = B.) Chymopapain is an acceptable treatment for
such patients, but less efficacious than standard or microdiscectomy. If
chymopapain is being considered, testing patients for allergic sensitivity to
this substance can reduce incidence of anaphylaxis. (Strength of Evidence = C.) Percutaneous discectomy is significantly less efficacious than
chymopapain in treating patients with lumbar disc herniation. This and other
new methods of lumbar disc surgery are not recommended until they can be
proven efficacious in controlled trials. (Strength of Evidence = C.) Patients with acute low back pain alone, who have neither suspicious findings
for a significant nerve root compression nor any positive red flags, do not
need surgical consultation for possible herniated lumbar disc. (Strength of
Evidence = D.) Surgery for herniated discs is
invasive and comprises all types of surgical and injection techniques to
remove or reduce the size of herniated intervertebral discs that compress
nerve roots. Included are standard discectomy, microscopic discectomy,
percutaneous discectomy, and chemonucleolysis (chymopapain injection). The
therapeutic objective is to relieve pressure on nerve roots and reduce pain
and possibly weakness and/or numbness in the lower extremities. Of 345 articles screened for this topic, 13
reporting on 10 studies met criteria for review.
[322],
[328] -
[339] In
addition, a meta-analysis article was reviewed by the panel.
[340] Other articles contained information used by the panel, but did not
meet article selection criteria.
[30],
[40],
[49],
[50],
[341] -
[345] Three of the studies reviewed
were randomized controlled trials (RCTs) that evaluated chymopapain as
compared with standard discectomy for patients with symptoms and findings of
lumbosacral radiculopathy. Crawshaw, Frazer, Merriam, et al.
[328]
found that at 1-year followup, 85 percent of those undergoing discectomy had
good or excellent results, compared to 44 percent of those receiving
chymopapain injections. Both groups had improved leg symptoms, but only the
discectomy group had significant improvements in back pain. Reported complications of herniated disc surgery include operative mortality,
wound infection, discitis, dural tears, nerve root injuries, thrombophlebitis
and pulmonary emboli, meningitis, cauda equina syndrome, psoas hematoma,
vascular injuries, and risks associated with transfusions. Hoffman, Wheeler,
and Deyo [340] stated that, overall, complications appeared to occur infrequently,
but that information on complications was often hard to interpret in the
studies reviewed, making determination of rates difficult. Lumbar discectomy may relieve
symptoms faster than continued nonsurgical therapy in patients who have severe
and disabling leg symptoms (associated with clinical examination findings of
definite lumbar nerve root compromise) and who have not improved after 4 to 8
weeks of adequate nonsurgical treatment. However, the evidence also showed that
in such nonemergent patients, there appears to be little difference in
long-term outcomes at 4 and 10 years between discectomy and conservative
care. Elderly patients with spinal stenosis who can adequately function in the
activities of daily life can be managed with conservative treatments. Surgery
for spinal stenosis should not usually be considered in the first 3 months of
symptoms. Decisions on treatment should take into account the patient's
lifestyle, preference, other medical problems, and risks of surgery. (Strength
of Evidence = D.) Surgical decisions for patients with spinal stenosis
should not be based solely on imaging tests, but should also consider the
degree of persistent neurogenic claudication symptoms, associated limitations,
and detectable neurologic compromise. (Strength of Evidence = D.) Spinal stenosis includes any constriction or narrowing of
the central spinal canal, the lateral recesses, or foramina resulting in
compression of nerve roots and/or the cauda equina. Surgery for spinal
stenosis may include various types of surgical techniques, usually including
decompressive laminectomy (sometimes combined with discectomy and/or spinal
fusion) done to alleviate the symptoms of neural compression. Of the 40 articles screened for this
topic, only one met criteria for review.
[346] In
addition, the panel reviewed an attempted meta-analysis on the topic.
[66] Other
articles contained information used by the panel, but did not meet article
selection criteria.
[347],
[348] No RCTs were found evaluating
surgery compared with nonsurgical treatment for spinal stenosis. However, a
controlled trial by Herkowitz and Kurz
[346]
compared decompressive laminectomy done with and without spinal fusion in
patients with chronic low back problems (mean symptom duration 3.0 years). None
of the patients had improved after adequate conservative treatment, and all
had findings consistent with degenerative spondylolisthesis and spinal
stenosis on CT, MRI, or myelogram. Internal fixation using metal devices was
not done as part of the fusion procedure. Immediately following surgery, the
fusion group reported significantly more pain relief in the back and legs than
did the nonfusion group. At long-term followup (mean followup time of 3.0
years), the percentage of patients reporting excellent or good outcomes was
significantly greater for the fusion group than for the nonfusion group (96
percent compared with 44 percent). Complications were also reviewed in the
Turner, Ersek, Herron, et al.
[66] meta-analysis. Death as a direct result of the surgery was rare, with
a mean in-hospital mortality of 0.32 percent. Other reported complications of
spinal stenosis surgery included dural tears (mean 0.32 percent), deep
infection (mean 5.91 percent), superficial infection (mean 2.3 percent), and
deep vein thrombosis (mean 2.78 percent). No RCTs were found comparing
surgery with nonsurgical treatment for spinal stenosis. Symptoms of severe and
persistent spinal stenosis may either remain the same, gradually worsen, or
improve with time. The duration of symptoms for most patients who have surgery
for lumbar spinal stenosis exceeds 1 year. This surgery is not commonly
considered within the first 3 months of symptoms. In the absence of fracture, dislocation,
or complications of tumor or infection, the use of spinal fusion is not
recommended for the treatment of low back problems during the first 3 months
of symptoms. (Strength of Evidence = C.) Spinal fusion should be
considered following decompression at a level of increased motion due to
degenerative spondylolisthesis. (Strength of Evidence = C.) Lumbar spinal fusion surgeries use bone grafts, and are sometimes
combined with metal devices, to produce a rigid connection between two or more
adjacent vertebrae. The therapeutic objective of spinal fusion surgery for
patients with low back problems is to prevent any movement in the
intervertebral spaces between the fused vertebrae, thereby reducing pain and
any neurologic deficits. Various theoretical rationales are given for the use
of fusion in patients with low back problems. One theory postulates that in
cases of significant spinal instability (abnormally increased motion at an
intervertebral level), fusion prevents painful compression of the neural
structures. Another controversial theory holds that, in some cases, back
symptoms arise from the disc itself and fusion relieves symptoms by greatly
reducing forces compressing the disc. Of the 129 articles screened for this topic, 3 met criteria for review.
[346],
[349],
[350] In
addition, a meta-analysis article was reviewed.
[351] Other articles contained information used by the panel, but did not
meet article selection criteria.
[352]-
[356] One RCT evaluated the rate of
fusion with and without Knodt rods in patients with a diagnosis of multiple
level foraminal stenosis.
[349] All patients were treated by wide decompressive laminectomy,
foramenotomy and bilateral-lateral fusion from L3 to the sacrum. The rates of
fusion, patient-reported functional status, and the lengths of postoperative
hospital stays were not significantly different between the two groups. Turner,
Ersek, Herron, et al.
[351]
indicated that complications are frequent with lumbar spinal fusions. Based on
a review of a large case series, the mean rates for the most common reported
complications were 7.3 percent for instrumentation failure and 10.8 percent
for bone graft donor site pain. The mean rates for other complications were 0.2
percent for in-hospital mortality, 1.5 percent for deep infection, 1.6 percent
for superficial infection, 3.7 percent for deep vein thrombosis/
thrombophlebitis, 2.2 percent for pulmonary embolus, 2.8 percent for neural
injury, 2.0 percent for graft extrusion, and 8.7 percent for other
complications. Spinal fusion is also considered an expensive procedure. There appears to be no good
evidence from controlled trials that spinal fusion alone is effective for
treatment of any type of acute low back problems in the absence of spinal
fractures or dislocation. In the opinion of the panel, there may be two
conditions where spinal fusion could be effective. The first is in cases of
combined degenerative spondylolisthesis, stenosis, and radiculopathy where
patients have decompressive laminectomy for spinal stenosis symptoms. The
second situation is in some young patients (generally under age 30) with
significant spondylolisthesis and severe leg pain who may receive some benefit
from stabilization procedures, although this has not been proven in controlled
trials. Social, economic, and psychological factors can significantly alter a
patient's response to back symptoms and to the treatment of those symptoms.
(Strength of Evidence = D.) In a patient with acute low back symptoms
and no evidence of serious underlying spinal pathology, the inability to
regain tolerance of required activities may indicate that unrealistic
expectations or psychosocial factors need to be explored before considering
referral for a more extensive evaluation or treatment program. (Strength of
Evidence = D.) Social, economic, and psychological
factors have been reported to be more important than physical factors in
affecting the symptoms, response to treatment, and long-term outcomes of
patients with chronic low back problems.
[357] There are indications that such nonphysical factors may affect
clinical outcomes for patients with acute low back symptoms
(Attachment A5). A heightened awareness among clinicians to the way such
factors may affect a patient's response to symptoms and treatment is therefore
warranted. None
of the articles screened about psychosocial factors in the assessment and
treatment of low back problems were controlled trials and therefore do not
meet panel review criteria for adequate evidence about efficacy. Five
articles, however, that included prospective cohort studies contained
information considered useful to the panel.
[23],
[50],
[358] -
[360] One
large prospective study
[358] of
asymptomatic individuals at a worksite found premorbid nonphysical factors
(i.e., measures of low work satisfaction and poor work performance reports) to
be the best predictors of individuals reporting back problems at work. In a
second study, [23] psychological variables measured early in the course of an acute low
back episode did not predict outcome, although other nonphysical factors, such
as educational level and perception of both job characteristics and "fault"
concerning the back problem, were strong predictors of outcome. A
population-based study
[359] also
suggested that psychosocial issues affect how individuals with low back
symptoms make decisions about working. The panel
found evidence that psychological, social, and economic (nonphysical) factors
can alter the response to symptoms and to treatment (including surgery) among
patients with acute low back problems. While such nonphysical factors have been
shown to affect outcomes, specific and effective interventions to address
these factors and alter patient outcomes have yet to be defined. No studies
that directly evaluated interventions aimed at psychosocial factors among
patients with acute low back problems were found.
The special studies are of two kinds. First are
tests to provide evidence of physiologic dysfunction such as neurologic
dysfunction, infection, inflammation, malignancy, or other systemic illness.
Second are tests to define a potential anatomic reason for the dysfunction
such as a herniated lumbar disc, spinal stenosis, infection, tumor, or
abdominal mass. As a result of diagnostic considerations, therapeutic
interventions including surgery may be recommended.
Except when
serious underlying pathology is suspected, special diagnostic tests are
usually not needed during the first month because it is not possible to
predict early on which patients will and will not improve during this period.
But those who are not improving at 1 month may include some who could benefit
from specific therapeutic interventions. Waiting longer to start the
diagnostic workup may delay recovery for these individuals. Special Studies: Tests for Evidence of Physiologic Dysfunction
Electrophysiologic Tests (EMG and SEP)
Panel findings and recommendations:
Literature Reviewed.
Four studies evaluated needle EMG.
[21],
[254],
[257],
[260]
Three studies evaluated H-reflex or F-wave tests.
[21], [254], [256] Two studies evaluated surface EMG.
[258],
[261] One
study evaluated SEPs.
[259] No
studies were found evaluating nerve conduction for assessing low back
problems. All articles meeting review criteria involved groups of patients
either with chronic problems or with unreported symptom duration. Evidence on Efficacy.
For needle EMG, four
articles evaluated the test's accuracy in diagnosing nerve root problems.
Aiello, Serra, Migliore, et al.
[21]
evaluated 25 patients who had clinical evidence of L3 and/or L4 nerve root
impairment. Needle EMG was abnormal in all 24 patients who had positive
findings at surgery, but predicted the exact levels of nerve root pathology in
only 9 percent of these 24 patients. One patient had a false-positive EMG with
no disc herniation found at surgery.
Aiello, Serra, Tugnoli, et al.
[254]
evaluated the accuracy of EMG for detecting and localizing nerve root
compromise in patients who had surgical findings of a single lumbar disc
prolapse at the L3-L4 level (100-percent true positive rate, 88-percent true
negative rate), with disc herniation at L4-L5 (96-percent true positive rate,
38-percent true negative rate) and with disc herniation L5-S1 (71-percent true
positive rate, 79-percent true negative rate).
Khatri, Baruah, and
McQuillen [257] evaluated outcomes at 1 year in patients with radicular leg pain who
had needle EMGs and computerized tomography (CT) scans and then went on to
have disc surgery or nonsurgical treatment (including conservative care and/or
epidural steroids). There were 35 patients who had abnormal EMGs and CT scan
findings of a herniated lumbar disc. Of the 16 patients treated with surgery,
81 percent were better at 1 year, while of the 19 who had nonsurgical
treatments only 47 percent reported improvement at one year. There were 24
patients whose EMGs and CT scans were both normal; none of these patients had
surgery, and at 1-year followup 67 percent were improved.
Young, Getty,
Jackson, et al.
[260]
evaluated 100 patients with clinical evidence of L5 or S1 radiculopathy and
found that needle EMG correctly predicted the level of nerve root pathology in
84 percent of the 95 patients with positive surgical findings. The wrong level
was predicted in seven patients, and in nine patients only one abnormal root
was detected when two were involved. EMGs were negative in all five patients
who had no root pathology noted at surgery.
In cases of radiculopathy
or neuropathy, EMG results may be unreliable in limb muscles until a patient
has had significant leg symptoms for over 3 weeks. Also, abnormal EMGs tend to
normalize over time. There is some evidence that greater accuracy can be
obtained in diagnosing lumbar nerve root compromise when information from
needle EMG is combined in a systematic fashion with information from imaging
tests and clinical findings, rather than relying on the results of each test
alone. [49], [50]
For H-reflex and F-wave tests, three articles reported on
accuracy in diagnosing nerve root problems. Aiello, Serra, Migliore, et al.
[21]
evaluated 25 patients with clinical evidence of L3 and/or L4 nerve root
impairment. H-reflex tests were abnormal on the affected side in 96 percent of
the 24 patients with L3 and/or L4 nerve root compromise confirmed at surgery,
but the test was also positive in the 1 patient with no nerve root pathology
noted at surgery (96-percent true positive rate, 0-percent true negative
rate).
Aiello, Serra, Tugnoli, et al.
[254]
evaluated H-reflex tests and EMGs for 50 patients in whom a single disc
prolapse was found at surgery. H-reflex tests were positive in 71 percent of 7
patients with L3-L4 disc herniations, 58 percent of 26 patients with L4-L5
disc herniations, and 100 percent of 17 patients with L5-S1 disc herniations.
In addition, by combining information from H-reflex tests and needle EMG, 30
percent of single disc prolapses could be determined accurately.
Braddom and Johnson
[256]
evaluated H-reflex tests in 25 patients with clinically suspected S1
radiculopathy. A normal range was established in 100 asymptomatic subjects. All
25 patients had H-reflex-test latencies greater than 2 standard deviations
above the mean for the control group. Only three patients were reported as
having surgery, and long-term followup results were not given.
For surface EMG, two articles evaluated efficacy in assessing patients with
low back symptoms. Arena, Sherman, Bruno, et al.
[255]
evaluated surface EMG of lumbar paraspinal muscles as a function of pain
state. Surface EMG results were not significantly able to differentiate back
pain patients with high pain states from those in low pain states. Sihvonen,
Partanen, Hanninen, et al.
[258]
evaluated both needle and surface EMG of lumbar paraspinal muscles in 87
patients with back pain (not radiculopathy) longer than 6 months, but who had
not had surgery, and in 25 controls with no history of back problems. When
compared to the asymptomatic controls, the patients with back pain had
significantly increased surface EMG activity while standing and immediately
after lumbar flexion.
For SEPs, the only article reviewed
[259]
evaluated accuracy in 18 patients with clinical findings of suspected spinal
stenosis who went on to have surgery. At operation, all patients were found to
have spinal stenosis. In all but 1 of the 18, SEPs had been positive
(94-percent rate). Potential Harms and Costs.
Summary of Findings.
SEPs appear to be useful in diagnosing spinal stenosis and spinal
cord myelopathy. However, F-wave tests and surface EMGs are not considered
effective methods of assessing acute low back problems.
Accuracy of
electrophysiologic testing is highly dependent on the skill with which the
examination is performed. Clinicians are urged to assess the qualifications of
the diagnostician before referring a patient with suspected neurologic
compromise. Bone Scan
Panel findings and recommendations:
Literature Reviewed.
Evidence on Efficacy.
The reference standard used depended on the clinical
condition to be assessed. Included were: clinical diagnoses;
[262]-
[264]
clinical followup or autopsy;
[265] and
biopsy with microbial cultures.
[266]
Schütte and Park [265] evaluated bone scans for two groups. One group
comprised 138 patients with a history of malignancy. In the other group, 38
patients with no previously recognized systemic disease had nonspecific low
back pain and normal x-rays, but with strong clinical suspicion of an
underlying serious condition causing the back pain. Of these 38 patients with
"nonspecific" low back pain, 14 (37 percent) were later found to have a
systemic disease. Of the 14 patients, 13 had elevated ESRs, but only 7 had
positive bone scans (all 7 also with high ESRs). Of patients with a history of
malignancy, 40 percent had positive bone scans determined on followup to be
metastases and 14 percent had osteoporotic rib or vertebral fractures.
The authors concluded that bone scan has a high yield in patients with known
malignancy. In patients where clinical suspicion of an underlying serious
problem was high, but who had no known malignancy and normal x-rays, ESR
detected 93 percent of those with systemic disease. Bone scan detected only 50
percent of these cases. The authors concluded that bone scan has a low yield in
patients with longstanding low back problems and normal x-rays and lab tests.
Whalen, Brown, McLeod, et al.
[266]
evaluated patients with low back pain who had extensive diagnostic workups
because of suspected spinal infections, and who then had open biopsy or
percutaneous needle aspiration for culture and microbiologic diagnosis.
Duration of symptoms before workup ranged from 2 weeks to 4 years (37 percent
with symptoms for less than 3 months). One subgroup of 19 patients had all of
these tests before spinal biopsy: technetium-
[99]m (Tc-
[99] m)
bone scan, indium-
[111] (In-
[111] )
white blood cell (WBC) bone scan, plain lumbar x-rays, and ESR. Of the 19
patients, 16 had spinal infections confirmed on culture of biopsy material.
For the 16 patients, true positive rates were: 81 percent for Tc-
[99]m bone scan, 19 percent for In-
[111] WBC
bone scan, 44 percent for plain x-rays, 82 percent for ESR > 20, and 56
percent for ESR > 50. False-negative rates for diagnosing spinal infection
were: 3 of 3 (100 percent) for Tc-
[99]m bone
scan, 14 of 17 (82 percent) for In-
[111] WBC
bone scan, 8 of 11 (73 percent) for plain x-rays, 2 of 2 (100 percent) for ESR
> 20, and 6 of 8 (75 percent) for ESR > 50. Half the infections were
attributed to prior spinal surgery or instrumentation, with the rest
attributed to hematogenous spread.
Miron, Khan, Wiesen, et al.
[264]
evaluated the accuracy of a quantitative bone scan technique, scintigraphy,
for diagnosing sacroiliitis in various groups of patients. First, 90 subjects
with no history of low back symptoms were evaluated with the test to establish
age- and sex-specific normal values for a sacroiliac index. A positive test was
defined as a sacroiliac index greater than two standard deviations above the
mean for normals. In evaluating patients with low back pain, the test was
positive in 50 percent of 18 patients who had signs and symptoms of active
sacroiliitis. The test was positive in only 7 percent (1 patient) of 14
patients who had low back pain, but no clinical, x-ray, or CT-scan evidence of
sacroiliitis. The authors concluded that this test has a low true positive rate
(50 percent), but high true negative rate (93 percent) for diagnosing
sacroiliitis.
Esdaile, Rosenthall, Terkeltaub, et al.
[262]
evaluated Tc- [99]m bone scan scintigraphy for diagnosing sacroiliitis. Normal values
for sacroiliac joint-to-sacrum ratios on scintigraphy were established in 18
controls with no clinical evidence of inflammatory back pain. These ratios were
found abnormally elevated in 66 percent of 12 patients considered to have
"possible" ankylosing spondylitis and in 46 percent of 22 patients considered
to have "definite" ankylosing spondylitis based on clinical and x-ray
findings. At the time of the initial testing, all patients were taking very
little or no anti-inflammatory medication. All were then treated with such
medication. The S1 joint-to-sacrum ratios significantly decreased after
treatment. The authors concluded that this technique is not a useful screening
technique to detect early ankylosing spondylitis. Potential Harms and Costs.
Summary of Findings.
Thermography
Panel
findings and recommendations:
Literature Reviewed.
Evidence on Efficacy.
The most recent meta-analysis
[268]
reviewed 81 relevant citations and analyzed 28 studies of thermography used
for diagnosing lumbar radiculopathy. Articles were graded excellent, good,
fair, or poor based on the following criteria: technical quality of the
reference test, uniform application of the reference test, independence of
interpretations, clinical description, cohort assembly, and sample size. Only
excellent and good studies were considered reliable sources of data on
diagnostic accuracy. No study was graded excellent, 1 study was graded good, 3
were graded fair, and the remaining 24 were graded poor. Because of the
methodological flaws in 27 studies, summary pooled statistics were not
reported. The only study considered reliable
[267]
found no discriminant value for thermography in diagnosing lumbar
radiculopathy. True positive and true negative rates were both 48 percent.
The four studies evaluating thermography in persons without back problems
found abnormal thermography of the lower limbs in 7 to 81 percent of these
asymptomatic subjects. Chafetz, Wexler, and Kaiser,
[269]
evaluating 15 asymptomatic subjects with no current back pain and no history
of back surgery or disability from back pain, found that 40 percent had
abnormal thermograms.
Harper, Low, Fealey, et al.
[270]
evaluated thermography in 37 asymptomatic subjects (carefully screened for no
history of back pain, back surgery, or disease or injury affecting the lower
extremities) as well as in 55 patients with clinically suspected
radiculopathy. All thermograms were interpreted independently by five readers
experienced in thermography who were blinded to all clinical data. The
different readers interpreted thermograms as probably or definitely abnormal
in 56 to 81 percent of the asymptomatic controls.
Perelman, Adler, and
Humphreys [271] evaluated thermography in 16 asymptomatic subjects with no low back
complaints and found 25 percent of these subjects to have abnormal
thermograms. Tests were considered abnormal if the thermogram had an asymmetric
visual pattern, but temperature differences were not measured. So, Aminoff,
and Olney [272] evaluated thermography in 30 patients with symptoms of lumbar
radiculopathy and in 27 asymptomatic controls. Thermogram readers were blinded
to clinical data. Abnormal thermograms, defined as temperature differences
between sides greater than three standard deviations from the mean for all
asymptomatic subjects, were found in 7 percent of the asymptomatic subjects. Potential Harms and Costs.
Summary of Findings.
Special Studies: Tests to Provide Anatomic Definition
Abnormal findings on anatomic studies such as MRI, CT,
myelography, and discography may be misleading, however, if they are not
corroborated with evidence of physiologic abnormality from the medical
history, physical examination, or physiologic tests. One problem with imaging
studies is that in many patients, there is an inability to find any defects.
Another problem is the lack of a "gold standard" in determining if an anatomic
defect seen on imaging tests is actually the cause of symptoms. Anatomic
abnormalities of the lumbar spine, such as degenerative changes and bulging or
herniated discs, are found to increase with aging on x-rays and other imaging
tests in subjects asymptomatic for low back problems.
[273]- [275]
Several studies stress the importance of not relying too
heavily on imaging studies alone for assessment when nerve root compromise is
suspected.
[30], [40], [49]
, [50]
The anatomic level of imaging study findings must correspond to the side and
the level of concern physiologically detected through the history, physical
examination, or other physiologic methods. Plain X-Rays
Panel findings and recommendations:
Literature Reviewed.
Evidence on Efficacy.
Hansson, Bigos, Beecher, et al.
[281]
evaluated the degree of lumbar lordosis seen on x-rays in three groups of
age-matched men engaged in heavy labor jobs. They included 200 asymptomatic
subjects who had preemployment x-rays, 200 patients seen for acute low back
problems, and 200 patients with low back disability longer than 6 months.
Films were read by back specialists blinded to all other data. No differences
were found between groups in the degree of lordosis noted on x-ray.
Deyo and Diehl
[278]
evaluated the use of a set of criteria based on medical history questions for
selectively ordering x-rays in 621 patients presenting to a hospital emergency
room with low back pain (patients with urinary tract symptoms excluded). The
11 criteria, any one of which would prompt an early x-ray, were: (1) age over
50, (2) significant trauma, (3) neuromotor deficits, (4) unexplained weight
loss, (5) suspicion of ankylosing spondylitis, (6) drug or alcohol abuse, (7)
history of cancer, (8) use of corticosteroids, (9) temperature greater than or
equal to 100 F, (10) a return visit for the same problem within 1 month and
not improved, and (11) patients seeking compensation for back pain.
X-ray findings were considered therapeutically important if they detected a
malignancy or fracture. Of these patients who had x-rays, 227 met one or more
of the criteria for x-ray, and 6.6 percent of these had therapeutically
important findings. Another 84 patients had x-rays even though they did not
meet any of the criteria. None of this group had therapeutically important
x-ray findings. The highest diagnostic yield was in patients over age 50. Of
the 119 patients in this group, 11 percent had therapeutically important
findings (13 fractures and 2 malignancies). Strict use of the selective
criteria would have resulted in x-ray studies in 390 patients.
Deyo
and Diehl [26] evaluated 1,975 walk-in patients at a public hospital, their chief
complaint back pain, in order to estimate the prevalence of cancer as an
underlying cause of back pain. A search of an institutional tumor registry at
least 6 months after the index visit identified 13 of these patients whose
back pain was attributed to cancer. History findings significantly associated
with the diagnosis of cancer were age over 50, prior cancer history,
unexplained weight loss, pain lasting more than 1 month, and no improvement
following conservative therapy. Laboratory test results significantly
associated with cancer were an ESR over 20 and anemia. The authors presented
an algorithm for ordering x-rays based on these history and lab test findings
that would have resulted in 22 percent of the total group receiving x-rays
including all patients who were found to have cancer.
Eleven articles
evaluated x-ray findings in patients with low back problems, compared with
asymptomatic subjects with no history of back problems. The findings of all of
these studies were similar. In general, x-ray findings correlated poorly with
low back problems.
[276], [277], [279], [281], [284], [285], [287], [288], [291], [292], [294]
In all these studies, degenerative changes were noted in some
persons with no history of low back problems whereas other persons with back
problems showed no degenerative changes. When groups of subjects of similar
age were compared, some studies show an increased prevalence of degenerative
changes of the lumbar spine in those who have had back problems, compared to
control groups with no history of back problems. Other studies found no
significant difference in prevalence of degenerative changes between these
groups.
These studies generally support the idea that degenerative
changes of the spine, as seen on x-rays or other imaging studies, are not by
themselves a cause of back pain. In fact, many authors suggest that
degenerative changes of the spine are merely signs of aging of the back.
Furthermore, degenerative changes were seen more commonly with increasing age
for both those with and those without a history of low back problems.
A possible exception is spondylolisthesis, a forward slippage of a vertebra on
the one below it. Two studies showed significantly higher prevalence of
spondylolisthesis in patients with low back problems than in asymptomatic
individuals. Torgerson and Dotter
[294]
found spondylolisthesis on x-rays in 4.9 percent of 387 symptomatic low back
pain patients, but in only 1.5 percent of 217 asymptomatic subjects. Magora and
Schwartz, [290] who evaluated adults currently working, found x-ray evidence of
spondylolisthesis in 3.1 percent of 648 subjects with a history of low back
pain patients, but in none of 376 subjects who had never had back pain.
Three other studies found no significant difference in prevalence of
spondylolisthesis between groups with low back problems and asymptomatic
controls. Biering-Sorensen, Hansen, Schroll, et al.
[276]
evaluated a group of men and women 60 years of age, including 308 with low
back pain and 358 asymptomatic controls. This study found an overall prevalence
of spondylolisthesis of 2.8 percent, with no significant difference between
the groups of symptomatic patients and controls. Bigos, Hansson, Castillo, et
al. [277]
found no difference in incidence of spondylolisthesis or other abnormalities
in the evaluation of age-matched males whether asymptomatic job applicants,
back injury claimants, or disabled patients with greater than 6 months'
duration of symptoms. Leboeuf, Kimber, and White
[285]
found spondylolisthesis on x-rays in 4.9 percent of patients with low back
pain and in 5.5 percent of asymptomatic controls. This difference was not
significant.
None of the studies reviewed on spondylolisthesis
attempted to measure spinal instability, and most did not compare groups in
terms of degree of spondylolisthesis. In addition, these studies did not
investigate whether there was any therapeutic benefit from determining if a
patient has spondylolisthesis (especially in patients with no findings that
suggest nerve root compression).
Some authors maintain that adults with
severe spondylolisthesis (degree of slip greater than 50 percent or a severe
increase in affected joint motion) may require special treatment.
[295]
However, the degree to which spondylolisthesis and abnormal motion may benefit
from special interventions is controversial and beyond the scope of this
guideline.
Other reported findings on lumbar x-rays for adult patients
with low back problems included: transitional vertebrae (lumbarization or
sacralization), spina bifida occulta, increased or decreased lordosis, mild or
moderate scoliosis and spondylolysis (an interarticular defect of the
posterior vertebral arch), and degenerative joint disease. These findings were
reported in similar frequency for 200 subjects without symptoms, for 200
subjects reporting back injury claim, and for 200 subjects disabled more than
6 months. This confirms multiple studies that have questioned both the use of
lumbar radiographs for preemployment screening and the diagnostic significance
of many radiologic findings.
[277]
Spondylolysis without spondylolisthesis is equally common in persons with
and without low back symptoms.
[277]
Spondylolysis has not been documented to be a cause or precursor of low back
problems in adults, and no special treatment is required. Potential Harms and Costs.
The cost of a lumbar spine x-ray is low compared to other imaging modalities
such as bone scan, CT, or MRI, and x-rays are more readily available. Summary of Findings.
The use of lumbar x-rays to screen for spinal
degenerative changes, congenital anomalies, spondylolysis, spondylolisthesis,
or scoliosis very rarely adds useful clinical information. Only 1 of 2,500
x-rays detects something not suspected on medical history and physical
examination that has an impact on patient care. Even in the rare cases where a
condition may be clinically significant, the history and physical examination
findings (that is, evidence of neurologic dysfunction) should dictate more
extensive diagnostic evaluation whether a routine x-ray screening is positive
or negative. Oblique lumbar x-rays, usually done to screen for spondylolysis,
rarely add useful clinical information in adults, and they double the x-ray
dose to the patient. Patients with spondylolisthesis can be safely treated in
the same fashion as those with other types of acute low back problems. Thus,
x-rays done specifically to screen for the presence of spondylolisthesis are
unnecessary in adults during the first 3 months of symptoms. CT, MRI, Myelography, and CT-Myelography
Panel findings and recommendations:
Introductory Discussion.
Significant technological advances have taken place in these imaging modalities
over the past several years. Kent, Haynor, Larson, et al.
[297] have
suggested technical criteria for the performance of these imaging tests to
assure a minimal level of quality. Studies of imaging tests were not considered
by the panel if the technical protocols were inadequately described or if the
protocols varied significantly among subjects within a study. The panel used
the following technical criteria for including studies of individual imaging
modalities:
The objective of using these imaging tests
for patients with acute low back problems is to define medically or surgically
remediable anatomic pathological conditions. Therefore, the tests are not done
routinely, but are generally used only for patients who present with one of
these three clinical situations:
This section assesses the
usefulness of the four imaging tests for diagnosing nerve root compromise due
to herniated discs or spinal stenosis. The use of imaging tests for evaluating
other serious conditions affecting the spine is beyond the scope of this
guideline and is not discussed in detail here. Imaging Tests to Evaluate Suspected Nerve Root Compromise Due to Lumbar Disc Herniation
Literature Reviewed.
Overall, 308 articles were screened for the subject of spinal imaging tests.
They included 141 for CT scan, 97 for MRI, and 70 for myelography (including
CT-myelography). Of the 308, there were 17 articles meeting criteria for review
that evaluated lumbar disc herniation as an anatomic cause for suspected nerve
root compromise.
[20],
[22],
[30],
[35],
[298] -
[310]
Other information used by the panel came from Sackett, Haynes, Guyatt, et al.
[311] All
of these studies used surgical findings as a reference test. Evidence on Efficacy.
Four articles evaluated plain myelography
alone.
[20], [30], [35]
, [301]
Three of the four evaluated only patients with no history of prior back
surgery. [20], [35]
, [301]
One included patients with prior back surgery.
[30]
In the four studies, lumbar disc herniations were found at
surgery in 68 to 96 percent of patients. Studies evaluating the true positive
rate and true negative rate of a diagnostic test are generally considered more
accurate when the target condition is present in 50 percent of the population
studied. [311] Only two of these four studies had prevalence rates for lumbar disc
herniation below 80 percent. Aejmelaeus, Hiltunen, Härkönen, et al.
[20]
studied a group with a 68-percent prevalence of disc herniation at surgery and
calculated the true positive rate of 75 percent and true negative rate of 55
percent for myelography in diagnosing this condition. Herron and Turner,
[30] found
a disc herniation at surgery 74 percent of the time, and the true positive
rate and true negative rate for myelography were 88 percent and 62 percent,
respectively. The remaining two articles found a lumbar disc herniation at
surgery in 84 to 96 percent of patients. In these studies, myelography was
calculated to have a true positive rate of 83 to 94 percent and a true
negative rate of 71 to 100 percent for diagnosing lumbar disc herniation. A
total of eight studies evaluated CT scan compared with myelography.
[22],
[298] -
[300],
[304],
[307] -
[309]
Only two of the studies looked at patient groups who had no prior back
surgery. [22], [307] Two studies included some patients with prior surgery.
[304], [309] The remaining four studies did not report on this variable.
For diagnosing lumbar disc herniation, all eight studies reported similar
ranges of true positive and true negative rates for both tests, and these
results were also similar to those from studies of myelography alone. The
number of subjects ranged from 37 to 195, and prevalence of lumbar disc
herniation found at surgery varied from 55 to 91 percent. The calculated true
positive rate of the tests for diagnosing lumbar disc herniation varied from
60 to 91 percent for CT scan and from 65 to 98 percent for myelography. The
true negative rate varied from 57 to 100 percent for CT scan and from 43 to
100 percent for myelography. One study allowed estimation of the added
diagnostic value of combining information from CT and myelography for the same
patient. [309] This study found similar accuracies for CT and myelography when
evaluated separately for diagnosing lumbar disc herniation (sensitivities 77
percent and 78 percent, specificities 83 percent and 72 percent). However,
when the results of both tests were evaluated together, the true positive and
true negative rates were 91 percent and 56 percent for a positive result
defined as either one of the two tests being positive. True positive and true
negative rates were 64 percent and 100 percent if a positive result was
defined as both tests being positive. This implies that the probability that a
true lumbar disc herniation will be detected on imaging is 77 percent if one
test is done and 91 percent if both tests are done. This also implies that the
probability of an imaging test showing a false-positive lumbar disc herniation
is 17 percent or 28 percent if one test is positive, but approaches zero if
both tests are positive.
The five remaining articles evaluated multiple
imaging tests done in the same patients.
[302],
[303],
[305],
[306],
[310] MRI
scan was compared to plain myelography,
[310] to CT-myelography,
[305] to
both plain and CT-myelography,
[306] and
to CT, plain myelography, and CT-myelography.
[303] Another study, also by Jackson, Cain, Jacobs, et al.,
[302] evaluated CT, myelography, and CT-myelography and compared them as
well to discography and CT-discography. The five studies all found no
significant differences between CT, MRI, and CT-myelography in terms of their
true positive rates and true negative rates for diagnosing lumbar disc
herniation although all these tests were better than plain myelography.
Jackson, Cain, Jacobs, et al.
[302]
found that for diagnosing lumbar disc herniation, CT-discography had a
significantly greater true positive rate (92 percent) than CT-myelography (78
percent), plain CT (72 percent), plain myelography (70 percent), or plain
discography (31 percent). However, in a subsequent study, Jackson, Cain,
Jacobs, et al.
[303] recommended MRI over other imaging tests as it is noninvasive and
exposes the patient to no ionizing radiation. No differences were found
between CT-discography, CT-myelography, CT, or myelography in the true
negative rates although all had a significantly higher true negative rate than
plain discography. Imaging Tests to Evaluate Suspected Spinal Stenosis
Literature Reviewed.
Lumbar spinal stenosis involves impingement of the cauda equina
nerves in the spinal canal, lateral spinal canal, or neural foramina. This is
usually a degenerative condition resulting from ligamentous infolding and bony
hypertrophy commonly seen in persons over age 60. Spinal stenosis is
occasionally developmental, due to congenitally short pedicles, and can affect
younger individuals.
One meta-analysis on the accuracy of CT, MRI, and
myelography for diagnosing lumbar spinal stenosis in adults was reviewed
[297]. Of
the 116 articles the authors screened for this meta-analysis, 14 studies met
their inclusion criteria for review.
[273],
[275],
[306],
[309],
[312] -
[321] Evidence on Efficacy.
In their meta-analysis, Kent,
Haynor, Larson, et al.
[297] concluded that estimates of accuracy of the imaging tests for
diagnosing spinal stenosis were imprecise and that all 14 studies had
methodological flaws (all judged to be of fair or poor quality). However,
based on data available, the meta-analysis found CT and MRI of similar
accuracy for diagnosing spinal stenosis (true positive and true negative rates
approximately 90 percent and 80 percent) and plain myelography with lower
accuracy. The authors cautioned that because of bias, estimates of test
accuracy obtained by the meta-analysis were likely to be too high. Spinal Imaging Findings in Asymptomatic Subjects
Literature Reviewed.
Six articles were
found that evaluated lumbar spinal imaging findings in asymptomatic subjects
with no low back symptoms. These studies included one evaluating CT scan,
[275] four
on [sup]MRI, [273], [291], [322], [323] and one for plain myelography.
[274]
Other articles contained information used by the panel, but did not meet
article selection criteria.
[30],
[40],
[49],
[50] Evidence on Efficacy.
Wiesel, Tsourmas, Feffer, et al.
[275]
evaluated readings of CT scans for 52 subjects with no history of low back
problems, with all scans read independently by three neuroradiologists blinded
to other data. For those under age 40, herniated discs were diagnosed in an
average of 19. 5 percent of subjects (range for the three readers, 13 to 24
percent). For subjects over age 40, those who had abnormal findings averaged 50
percent (with a range of 30 to 82 percent among the readers). Included were 27
percent of subjects diagnosed with herniated discs, 10 percent with facet
joint hypertrophy, and 3 percent with spinal stenosis. Technical quality of
this study was considered adequate.
Boden, Davis, Dina, et al.
[273]
evaluated readings of MRI scans in 67 subjects with no history of back
problems. Scans were read by three neuroradiologists blinded to all other data
after the scans were randomly mixed with scans of symptomatic patients who had
proven back pathology. Of the asymptomatic subjects, 35 were age 20 to 39, 18
were age 40 to 59, and 14 were age 60 and over. The percentages for each of
the above age groups were reported respectively by neuroradiologists as: a
definite or probable abnormality in 22 percent, 22 percent, and 57 percent;
bulging disc in 56 percent, 50 percent, and 79 percent; disc herniation in 21
percent, 22 percent, and 36 percent; degenerative disc in 34 percent, 59
percent, and 93 percent; spinal stenosis in 1 percent, 0 percent, and 21
percent. This study was considered of good technical quality.
Paajanen,
Erkintalo, Dahlström, et al.
[291]
evaluated MRI scans in age-
[20] male
military conscripts including 75 subjects with low back pain and 34 controls
with no history of low back problems. Five intervertebral discs, from L1-L2 to
L5-S1, were evaluated for each subject. Disc degeneration, indicated by reduced
MRI signal intensity for the disc, was found in 57 percent of patients with
low back problems and 35 percent of controls. The authors stated that it was
unclear if the positive findings in controls represented pathological
processes or merely normal aging changes that did not predispose to future low
back problems. The technical quality of the MRI scans in this study was
considered suboptimal because low field strength MRI (0.02 T) was used.
Powell, Wilson, Szypryt, et al.
[322]
evaluated the MRI scans in 302 women who had no symptoms of low back problems,
but who had the scans done for nonback obstetrical problems. Using reduced MRI
signal intensity of the disc as an indication of disc degeneration, the
authors found one or more degenerative discs in 34 percent of women age 21 to
30, in 60 percent of women age 31 to 40, and in 95 percent of women by age
70. Bulging discs were found on MRI in 11 percent of 82 pregnant women and 13
percent of 56 women who had never been pregnant (these data not presented by
age group).
Weinreb, Wolbarsht, Cohen, et al.
[323]
evaluated MRI findings in 45 pregnant women age 20 to 39 and in 41 nonpregnant
women age 19 to 40 with no current low back symptoms. Three intervertebral
disc levels, L3-L4, L4-L5, and L5-S1, were evaluated for all subjects. No
significant differences were found between pregnant and nonpregnant women in
terms of the percentage with lumbar disc herniation (9 percent compared with
10 percent) or disc bulging without herniation (44 percent in each group). The
technical quality of this study was considered suboptimal because testing
protocols varied between subjects and low field strength MRI (0.35 T) was
used.
Hitselberger and Witten
[274]
reviewed lumbar myelograms done in 300 patients with no prior history of
radiculopathy. The technical quality of this study was considered poor because
oil-based contrast media were used, which are less sensitive than more modern
techniques. Still, 24 percent had myelographic evidence of lumbar disc
herniation, 9.3 percent had spinal stenosis without a history of radicular
symptoms (1 of 300 with a complete block of the dye). This study was of
limited value because findings were not given by specific age groups, and the
age range of subjects was 18 to 76 with a mean age of 51.
Degenerative
discs, bulging discs, and even herniated discs are part of the aging process
for the spine and may be irrelevant findings; they are seen on imaging tests
of the lumbar spine in a significant percentage of subjects with no history of
low back problems. Therefore, abnormal imaging findings seen in a patient with
acute low back problems may or may not be related to that individual's
symptoms. A herniated disc noted on an imaging test is more likely to be
associated with a clinically significant nerve root compromise in patients
when there are other findings (such as leg pain, positive straight leg
raising, neurologic deficits, or a positive electrodiagnostic test) that
suggest physiologic nerve root compromise.
[30],
[40],
[49],
[50] Potential Harms and Costs.
Factors that may influence
the decision on which imaging test to use in diagnosing low back problems
include the following: (1) tissue of greatest interest for imaging (CT better
for bone, MRI better for imaging neural tissues and bone marrow and for
diagnosing tumor or infection); (2) claustrophobia (more of a problem for
MRI); (3) obesity (both CT and MRI scanners have a maximum table weight, so
that extremely heavy patients may need to have myelography); (4) presence of
internal metallic objects such as implanted medical devices, metallic surgical
clips, or metallic objects or fragments in the eye, which can be a major
problem for MRI (and sometimes for CT); (5) preference of the consultant and
of the patient; (6) availability, cost, and potential side effects of the
test.
CT-myelography and myelography have a higher risk of
complications than CT or MRI (for example, post-spinal-tap headaches and
adverse reactions to contrast media). For CT scan, potential harms include
minimal x-ray exposure (including gonadal radiation exposure in females).
Amount of exposure (less than two rads) is similar to that from two standard
x-ray views of the lumbar spine. For MRI scan, there have been no clearly
documented adverse health effects. Long-term effects of magnetic field exposure
from MRI are unknown, but this test is generally believed to involve minimal
risk. CT scan, MRI scan, CT-myelography, and plain myelography are all
considered moderate to expensive in cost. Summary of Findings.
Given the benign natural history of acute low back problems,
with 80 to 90 percent of patients expected to improve at 1 month even without
treatment, routine spinal imaging tests are not generally necessary during the
first month of symptoms except when a red flag (suggesting a medically
emergent condition) is noted on medical history and physical examination.
After 1 month of symptoms, the use of imaging tests may be appropriate when
surgery is being considered for a specific detectable loss of neurologic
function or to further evaluate possibly serious spinal pathology in the
presence of red flags. Discography
Panel findings and recommendations:
Literature Reviewed.
Evidence on Efficacy.
In the only study to meet panel review criteria, Colhoun,
McCall, Williams, et al.
[324]
evaluated the results of discography using surgical findings and long-term
clinical outcomes as independent reference standards. This study evaluated
discography in 195 patients with persistent low back pain (symptom duration
not otherwise specified), but with no history of prior back surgery. All
patients went on to have back surgery (spinal fusion for 82 percent of
patients, laminectomy and/or discectomy for the remaining patients). All
patients were followed for 2 to 10 years postoperatively (results not
presented separately by type of operation). Patients who had spinal fusion
were excluded from the study if the surgery was deemed to be technically
unsuccessful (that is, if there was x-ray evidence of pseudoarthrosis at the
site of attempted fusion). Treatment success on followup was noted in 89
percent of 137 patients who had positive pain response on discography and
abnormal discograms, compared to 52 percent of 25 patients who had negative
pain response but abnormal discograms and 50 percent of 12 patients who had a
negative pain response and normal discography.
Holt
[326]
evaluated discograms done in 30 male prison inmate volunteers who had no prior
history of low back problems, normal lumbar x-rays, and normal back
examinations. Their age range was 21 to 49, average age 26. Discography was
attempted at the L3-L4, L4-L5, and L5-S1 disc levels for each subject. Of the
71 successfully performed discograms, a positive pain response was noted in 37
percent of the discs injected. All of these also had abnormal discograms
(showing either degenerative changes or disc rupture). The remaining 63
percent of discs injected had negative pain responses and normal discograms.
Holt interpreted these results as showing a 37-percent false-positive rate for
discograms. However, in a reevaluation of this study, Walsh, Weinstein,
Spratt, et al.
[327] noted inconsistencies in Holt's data and recalculated the
false-positive rate as either 26 percent or 4 percent depending upon
assumptions made.
Walsh, Weinstein, Spratt, et al.
[327]
evaluated CT-discography done in 7 patients with low back pain and in 10
"asymptomatic" subjects with no history of low back problems. Discography was
attempted at three lumbar disc levels for each subject, with a water-soluble
nonionic contrast media. Disc injection was videotaped, and the subjects' pain
reactions and discograms were later read independently by two orthopedic
surgeons and three radiologists blind to all other data. Discography in the
patients was considered positive if the discogram was abnormal, if there were
two or more videotaped pain behaviors, and if disc injection provoked the
patient's typical pain. In asymptomatic subjects, discography was considered
positive if the discogram was abnormal and there was significant pain noted on
disc injection. Discography was positive in all 7 patients with low back
problems (65 percent of the 13 discs successfully injected being abnormal). In
the asymptomatic subjects, 50 percent had an abnormal discogram (17 percent of
the 30 successful discograms for this group), but none had positive pain
response on disc injection. Therefore, none of the asymptomatic subjects was
considered to have positive discography (that is, no false- positive tests). Potential Harms and Costs.
Summary of Findings.
There is no good evidence that discography is useful to promote better
treatment outcomes in patients with acute low back problems. Colhoun, McCall,
Williams, et al.
[324]
noted more successful outcomes after back surgery for those with a positive
discography, but these were presumably patients with chronic problems (as they
had persistent pain). The rationale for using discography is to select
patients who would most benefit from spinal fusion. Yet, in the Colhoun
article, the predictive value of positive discography in establishing which
patients do well after spinal fusion cannot be determined accurately because
18 percent of patients did not have fusions and outcomes were not reported
separately for fusions and discectomies. Moreover, the two articles on
discography in asymptomatic subjects report a substantial percentage of
subjects who had positive discograms although they had never had low back
problems.
In summary, there is limited evidence that discography can
help select patients who would benefit from spinal fusion and no evidence that
it is helpful in patients with acute low back problems. Potential serious
risks from discography, including disc infection, have been identified. The use
of discography or CT-discography to diagnose herniated discs appears to offer
no significant advantage over other imaging methods with less potential risk
of harm. Surgical Information
Surgery for Herniated Disc
Panel
findings and recommendations:
Literature Reviewed.
Evidence on Efficacy.
Ejeskär, Nachemson, Herberts, et al.
[329]
found that at 6 months, 56 percent of patients initially receiving chymopapain
injections had undergone surgery due to unrelieved symptoms (all of these
patients with disc herniation confirmed at surgery). When patients were
followed up during the first 6 months before any treatment crossovers
occurred, those receiving discectomy reported significantly greater
improvement in symptoms than those receiving chymopapain injections.
Van Alphen, Braakman, Bezemer, et al.
[336]
found that at 1-year followup, physicians rated significantly more of the
patients in the discectomy group as having good results from their initial
treatment compared with the chymopapain group (85 percent compared with 63
percent). Also, 25 percent of the chymopapain group required subsequent
discectomy while only 3 percent of the discectomy group needed a second
operation. Open discectomy following prior failed chymopapain injection was
successful in 44 percent of the cases.
Another RCT (reported in
Fraser; [330] Fraser; [331] and Gogan and Fraser
[332])
evaluated chymopapain injections compared with intradiscal saline injections
in patients who had sciatica and evidence of a herniated lumbar disc, but who
had not improved after 6 months of conservative therapy. Treatment success
rates were significantly better for the chymopapain group than for the saline
group at 6-month followup (80 percent compared with 57 percent), at 5-year
followup (73 percent compared with 47 percent), and at 10-year followup (80
percent compared with 34 percent). Also, significantly fewer patients required
a laminectomy for unrelieved symptoms in the chymopapain group compared with
the saline group when followed up at 2 years (20 percent compared with 40
percent) and at 10 years (20 percent compared with 47 percent).
A
double-blind RCT by Javid, Nordby, Ford, et al.
[333] evaluated chymopapain injection compared with intradiscal saline
injection in 108 patients with sciatica who had not improved after at least 6
weeks of conservative treatment including 2 weeks of bed rest. All patients
had positive straight leg raising, a neurologic defect on physical
examination, and myelogram evidence of a single lumbar disc herniation. At 6
months postinjection, the treatment success rate was significantly better for
the chymopapain group compared with the saline injection group (83 percent
compared with 42 percent).
Revel, Payan, Vallee, et al.
[334]
evaluated chymopapain injections compared with percutaneous discectomy in 141
patients with sciatica who did not improve after 1 month of conservative
treatment. Overall success rates were significantly better for the chymopapain
group than for the percutaneous discectomy group at both 6-month followup (61
percent compared with 44 percent) and 1-year followup (66 percent compared
with 37 percent). Also, fewer patients in the chymopapain group required open
laminectomy within 1 year due to unrelieved symptoms as compared with the
percutaneous discectomy group (7 percent compared with 33 percent).
Only one RCT (reported by Weber
[338],
[339] )
compared standard discectomy with conservative (nonsurgical) care. This study
looked at 280 patients who consecutively presented to a hospital neurology
department with severe sciatica and clinical findings of possible or definite
L4-L5 or L5-S1 disc herniation. All patients were initially hospitalized for 2
weeks of conservative treatment including 1 week of strict bed rest. After 2
weeks, 87 patients with possible but indefinite disk hernia who had shown
continuous improvement were assigned to continued conservative care, and
discectomy was performed for 67 patients who were deemed by their surgeon to
have emergent indications for immediate surgery (intolerable pain, suddenly
occurring or progressive muscle weakness, or impending bladder or anal
sphincter paresis). This left a group of 126 subjects who had continued sciatic
symptoms provoked by mild exercise, sitting, or Vasalva maneuver and with
myelograms that showed definite disc herniations consistent with their
clinical findings of neurologic dysfunction. Patients in this latter group
were randomly assigned to receive either standard discectomy or continued
conservative treatment.
Of these 126 subjects with definite disc hernia
who were randomized, Weber
[338],
[339]
found good or fair results in 61 percent of the nonsurgery group and in 90
percent of the discectomy group at 1-year followup. This difference was no
longer significant on followup at 4 years (86 percent compared with 89
percent) or 10 years (93 percent compared with 92 percent). At 4-year followup,
considerable sciatic pain was still reported by 9 to 10 percent of each group
and considerable low back pain by 11 to 12 percent of each group. At 10-year
followup, no patients in either group reported these symptoms. During the first
year, 26 percent of the nonsurgery group demanded discectomy because of
unrelieved sciatic pain. On followup, good or fair results were reported for 82
percent of this group at 4 years and for 100 percent of the group at 10
years.
Tullberg, Isacson, and Weidenhielm
[335]
evaluated microdiscectomy compared with standard discectomy in a RCT of
patients with sciatica who had not improved after 2 months of conservative
treatment and had evidence on CT scan of a single-level disc herniation. At
1-year followup, no significant difference was noted between microdiscectomy
and standard discectomy groups in terms of patients reporting excellent or
good results (86 percent compared with 90 percent), mean postoperative time
off work (10.4 weeks compared with 10.1 weeks), or mean improvement in visual
analog pain scale ratings over the prior year.
A meta-analysis for
herniated lumbar disc surgery by Hoffman, Wheeler, and Deyo
[340]
found only two RCTs.
[336],
[338],
[339]
This meta-analysis concluded that patients with severe leg symptoms and
confirmed lumbar disc herniation experienced faster symptom relief and
improved functioning if they underwent standard discectomy rather than
conservative treatment. The meta-analysis stated that there was inadequate
evidence available to determine the efficacy of microdiscectomy or
percutaneous discectomy for treating low back problems. However, percutaneous
discectomy was noted to have a higher reoperation rate than standard
discectomy. Discectomies were noted to be relatively safe procedures, but
reoperations were also reported to be fairly common.
Several studies
have emphasized the role psychosocial factors play in influencing the outcome
of surgery for herniated disc.
[30],
[40],
[49],
[50] In
fact, Spengler, Ouellette, Battié, et al.
[50] found that psychological factors, especially elevated hysteria or
hypochondriasis scales on a Minnesota Multiphasic Personality Inventory
(MMPI), were better predictors of surgical outcome than were findings on
imaging studies. Potential Harms and Costs.
A
community-based study in Michigan, which reviewed the hospital discharge
records of over 28,000 patients who had a lumbar disc surgery in 1980,
reported incidence rates of 0.06 percent for mortality, 0.3 percent for
infections treated with intravenous antibiotics, and 0.3 percent for major
neurologic complications. A similar study of hospital discharge records in
Washington State found an overall mortality incidence of 0.07 percent for
spinal surgery.
[345]
The reported complications for chymopapain therapy include
allergic reactions (some resulting in death), discitis, thrombophlebitis,
pulmonary embolus, neurologic injury, vascular injury, and transverse
myelitis.
[341]- [344] Skin tests for sensitization before chymopapain injection are
reported to significantly reduce the risk of allergic reaction. Transverse
myelitis is uncommon, and the risk factors for this are unclear.
Complication rates for discectomy are generally low. Complication rates for
chymopapain are also low, but the use of chymopapain has decreased drastically
in the United States because of concerns about transverse myelitis and
anaphylactic reactions. The use of tests for allergic sensitization to
chymopapain before this treatment may reduce the risk of allergic reaction.
Surgery for herniated discs is considered an expensive treatment. Summary of Findings.
There are direct methods of nerve root decompression and indirect
methods. The best results from herniated disc surgery were with direct methods
of standard discectomy and microscopic discectomy with no significant
difference in results noted between these procedures. Studies indicate that
the direct method of standard discectomy produces better results than the
indirect method of chymopapain. Chymopapain is better than placebo injections
of saline or the indirect method of percutaneous discectomy. Rates of initial
treatment failure requiring a subsequent surgery are higher for chymopapain
than for discectomy.
No studies to date have shown that any of the
newer indirect methods of disc surgery, such as indirect automated
percutaneous and percutaneous laser discectomy, produce better results than
standard discectomy or chymopapain in appropriate patients.
Patient
preference does and should play a large role in the surgical decision, but
only if adequate information is available about efficacy, risks, and
expectations. Surgery for Spinal Stenosis
Panel findings and recommendations:
Spinal
stenosis is generally a degenerative condition affecting patients over age 60
and is usually related to a variety of age-related changes in spinal anatomy
that combine to cause compression of the cauda equina in the lumbar spinal
canal and neuroforamina. These age-related changes may include disc bulges and
herniations, thickening of the infolded ligamentum flavum, degeneration of the
facet joints and joint capsules, osteophytes, and occasionally degenerative
spondylolisthesis. There are also some younger individuals with severe
congenital narrowing of the spinal canal who have spinal stenosis symptoms,
but this is uncommon.
The primary symptoms of severe spinal stenosis
are neurogenic claudication (leg pain with walking or standing, relieved by
sitting or spinal flexion) and occasionally weakness of the legs. Literature Reviewed.
Evidence on Efficacy.
An attempted meta-analysis reviewed
74 studies involving patients who had decompressive laminectomy for lumbar
spinal stenosis.
[66] The
authors of the attempted meta-analysis found three prospective studies, but no
randomized controlled trials comparing surgery with conservative treatment.
Therefore, no conclusions could be drawn as to the relative benefits and risks
of surgery compared with conservative treatment. One study reported that of 27
unoperated patients with spinal stenosis, 19 remained unchanged, 4 improved,
and 4 deteriorated during a followup period of 10 to 103 months with a mean of
49 months. [347] A comparison of these outcomes by Turner, Ersek, Herron, et al.
[66] suggested that patients may show more improvement with surgery, but
conservative management may be a reasonable alternative.
Of the 74
studies reviewed by Turner, Ersek, Herron, et al.,
[66] 31 provided sufficient information to calculate the proportion of
patients with good-to-excellent as compared with poor-to-fair outcomes.
Criteria for classifying outcomes into categories of excellent, good, fair,
and poor varied across studies, making it difficult to combine and compare
studies. When results were classified using a standard method for each article,
the percentage of patients whose outcomes were classified as good to excellent
varied from 26 to 100 percent (mean of 64 percent) for the 31 articles.
Most patients who have surgery for lumbar spinal stenosis have had their
symptoms for over a year. It is not a common surgical consideration within the
first 3 months of symptoms.
[66]
Reoperation rates after spinal stenosis surgery (which were reported in 25
of the articles) ranged from 0 to 21 percent (with a mean of 8 percent).
However, the authors speculated that these rates probably underestimated the
true reoperation rates because of some followup periods that were very short.
The attempted meta-analysis by Turner, Ersek, Herron, et al.
[66] concluded that in patients with severe symptoms from lumbar spinal
stenosis, decompressive laminectomy appears to be beneficial for many patients
by reducing pain and increasing the ability to function and is probably
associated with an acceptably low complication rate.
There are also
some data showing that although short-term results from spinal stenosis
surgery may be good for most patients, for many patients there may be a
progressive deterioration over time. A case series by Katz, Lipson, Larson, et
al.,
[348] which followed 88 patients over age 55 who had decompressive
laminectomy for symptoms of degenerative spinal stenosis, found that 89
percent of patients reported good outcomes (defined as absence of severe pain
and no repeat operations) at 1-year followup, but only 57 percent of patients
reported good outcomes at 3- to 6-year followups. Potential Harms and Costs.
The complication rate for
spinal stenosis surgery is 10-15 percent, with half the complications
being serious or life-threatening problems. These complications can result from
the general anesthetic, the spinal problem itself, or coexisting medical
problems. The high rate of complications may be because of the older age of
this group.
Surgery for spinal stenosis is considered expensive. Summary of Findings.
For patients with a
history of severe and persistent symptoms of neurogenic claudication who
undergo spinal stenosis decompressive laminectomy, the most likely outcomes
are less leg pain and improved walking tolerance. However, there is some
indication that these results tend to deteriorate over time.
The
potential for serious complications from this procedure is considered to be
acceptably low, although the rate is higher than for other procedures
primarily because this operation is usually done in older individuals. Spinal Fusion
Panel
findings and recommendations:
Literature Reviewed.
Evidence on Efficacy.
A controlled trial by Herkowitz and Kurz
[346]
compared laminectomy with and without fusion in patients with chronic symptoms
(mean symptom duration 3.0 years) who did not improve after nonoperative
treatment and who had a positive imaging finding (myelogram and either CT or
MRI) consistent with degenerative spondylolisthesis and spinal stenosis.
Internal fixation using metal devices was not done as part of the fusion
procedure. Following surgery, the fusion group reported significantly greater
pain relief in the back and legs than did the nonfusion group. At mean
followup of 3.0 years, excellent or good outcome rates were significantly
greater for the fusion group than for the nonfusion group (96 percent compared
with 44 percent).
The third study meeting review criteria was a
nonrandomized trial comparing laminectomy with and without Knodt rod fusion in
patients with chronic symptoms, leg pain or neurologic deficit, who did not
improve after 3 months of conservative care and who had a positive imaging
finding (EMG and myelogram or CT) for a herniated disc.
[350] At
long-term followup (mean followup time of 4.9 years for the fusion group and
3.7 years for the nonfusion group), the percentages of patients reporting
satisfactory results (excellent or good) were not significantly different
between the two groups. There are serious design problems with this study,
such as the fusion group having a significantly longer mean duration of
preoperative symptoms: 5.7 years compared with 1.3 years.
An attempted
meta-analysis on this topic
[351]
found only four nonrandomized studies comparing surgery with and without
fusion for herniated disc
[350],
[353],
[354],
[356]
Three of the four trials reported no significant difference in results between
the two groups. One trial did report significantly better results with fusion,
but the treatment groups were not comparable. The fusion group had
significantly more abnormal findings on x-ray, fewer positive straight leg
raising tests, longer duration of pain, and fewer workers' compensation
patients. [356] Potential Harms and Costs.
Summary of Findings.
Although the usual reasons stated for doing spinal fusion for
degenerative problems are instability of the spine and disc disease, there is
lack of scientific agreement on how to define spinal instability.
Spondylolisthesis is often implicated as a cause of instability, but it may or
may not have any detectable abnormal motion and the extent to which this
contributes to low back symptoms is controversial. Moreover, there is no good
evidence that patients who undergo fusion will return to their prior
functional level. It appears that fusion is not commonly considered for adults
within the first 3 months of symptoms except for fracture or dislocation.
[346], [350] Assessment of Psychosocial Factors
Panel findings and recommendations:
Literature Reviewed
Evidence of Efficacy
Several studies have detected a
strong correlation between the outcome of lumbar spine surgery and the
preoperative psychological status of the patient.
[50],
[360] Summary of Findings
Given such limited
information, the panel was55555 unable to recommend specific assessment tools
or interventions focusing on psychosocial factors potentially important for
patients with acute low back problems. Recognizing the impact such nonphysical
issues can have on outcomes, however, the panel recommended that clinicians be
aware of these factors, especially in patients whose recovery of activity
tolerance following an acute low back problem seems delayed. Further research
is needed to define specific methods of detecting nonphysical factors as well
as interventions that might improve outcomes for those patients slow to
recover from acute low back problems.
References
Shiqing X, Quanzhi Z, Dehao F. Xin SQ, Zhang Qz, Fan DH.
The Mercy Conference ~ Major Recommendations
Gaithersburg, Md: Aspen Publishers Inc; 1993.
Indus Med IMS Ind Med Surg 1970 Jun;39(6):253-8.
Cain JE, Becker GJ, Jacobs RR, [Montesano PX,] Cooper BR, McManus GE.
Glossary
- Acute low back problem.
- Activity limitation(s) due to low back symptoms (back pain or back-related leg pain) present less than 3 months.
- Back school.
- A structured educational program, usually in a group setting, designed to inform patients about low back problems.
- Biofeedback.
- The use of auditory and visual signals reflecting a patient's muscular activity to allow the patient to facilitate or extinguish this muscle action. In patients with low back pain, the objective is to reduce pain by reducing muscle tension.
- Cauda equina syndrome.
- Compression (usually due to the extrinsic pressure of a massive, centrally herniated disc) on a sheaf of nerve roots from the lower cord segments, often resulting in bilateral motor weakness of the lower extremities, saddle anesthesia, and urine retention or incontinence from loss of sphincter function.
- Chemonucleolysis.
- The injection of a proteolytic enzyme (e.g., chymopapain) into the herniated nucleus pulposus of a disc.
- CT-myelography.
- Computerized tomography done after contrast media has been injected into the dural sac.
- Diathermy.
- Therapeutic elevation of the temperature of deep tissues by means of high frequency shortwave or microwaves.
- Discography.
- The injection of a water-soluble imaging material directly into the nucleus pulposus of a disc to assess the extent of disc damage and characterize the pain response.
- Discectomy.
- The surgical removal of all or part of a herniated intervertebral disc compressing a nerve root. When microscopic or visually aided surgical techniques are used, this procedure is referred to as microdiscectomy. The procedure can also be done through a small incision using indirect visualization (percutaneous discectomy).
- Electromyography (EMG).
- An examination of the electrical activity of a motor unit, useful in determining the site of injury in a peripheral nerve and in detecting spinal nerve root lesions as well as primary muscle diseases. Needle EMG involves the insertion of needle electrodes into muscle; surface EMG uses surface electrodes instead of needle insertion.
- Ergonomics.
- The study of the proper and efficient use of the body in work and recreation, including the design and operations of machines and the physical environment.
- F-wave tests.
- The use of electrodiagnostic equipment to measure motor conduction through nerve roots, most frequently to assess proximal neuropathies.
- Facet joints.
- Synovial joints formed by the facets on the articular processes of contiguous vertebrae.
- H-reflex tests.
- The use of electrodiagnostic equipment to measure sensory conduction of a stimulus through nerve roots that then evoke a motor reflex, commonly employed to assess S1 radiculopathy.
- Herniated disc.
- Herniation of the central gelatinous material (nucleus pulposus) of an intervertebral disc through its fibrous outer covering (annulus fibrosis).
- Nerve conduction studies.
- Tests of peripheral nerves performed by stimulating the nerve at one point and measuring the action potential either at another point along the nerve (sensory conduction) or of the muscle innervated by the nerve (motor conduction).
- Neurogenic claudication.
- Symptoms of leg pain (and occasionally weakness) on walking or standing, relieved by sitting or spinal flexion, related to neural compression, usually spinal stenosis.
- Pain drawings.
- Drawings by patients depicting the severity, type, and location of their pain as a technique for assessing psychological involvement in the pain complaints.
- Radiculopathy.
- Dysfunction of a nerve root often caused by compression of the root. Pain, sensory impairment, weakness or depression of deep tendon reflexes may be noticed in the distribution of nerves derived from the involved nerve root.
- Saddle anesthesia.
- Loss of sensation in the skin over the perineum indicative of dysfunction of sacral nerve roots.
- Sciatica.
- Pain radiating down the leg(s) below the knee along the distribution of the sciatic nerve, usually related to mechanical pressure and/or inflammation of lumbosacral nerve roots.
- Sensory evoked potentials (SEP).
- The use of electrical stimuli applied to specific nerves or dermatomes to assess the normalcy of nerve responses.
- Spinal manipulation.
- Manual therapy for symptomatic relief and functional improvement of the back in which loads are applied to the spine using short or long lever methods. The selected spinal joint is moved to its end range of voluntary motion, followed by application of an impulse load.
- Spinal stenosis.
- A narrowing of the spinal canal that may produce a bony constriction of the cauda equina and the emerging nerve roots.
- Spondylolisthesis.
- Forward subluxation of the body of a lumbar vertebra on the vertebra below.
- Spondylolysis.
- A fracture or cleft in the vertebral body, often through the posterior vertebral arch, loosening its normally firm attachment to contiguous vertebrae.
- Straight leg raising (SLR).
- A procedure of stretching the sciatic nerve to see if radicular symptomatology is reproduced. Each hip is alternately flexed with the knee extended; the extent to which each leg can be lifted is noted. Reproduction of the patient's sciatica when the unaffected leg is lifted is evidence of a positive "crossed" straight leg raising test.
- Thermography.
- A procedure that images the infrared radiation (heat) emitted from body surfaces. In patients with low back problems, thermographic image patterns of the back and lower extremities are measured.
- Transcutaneous electrical nerve stimulation (TENS).
- A small battery-operated device, worn by the patient, which provides continuous electrical pulses via surface electrodes with the goal of providing symptomatic relief by modifying pain perception.
- Traction.
- When used for low back problems, intermittent or continuous force is applied along the axis of the spine in an attempt to elongate the spine. The type most commonly used for low back problems is pelvic traction in which a girdle around the patient's pelvis is attached to weights hung at the foot of the bed.
- Trigger point.
- A well localized point of tenderness. In low back problems, these points are usually located in the paravertebral areas.
- Visual analog scales.
- A visual means by which a patient can quantify pain. The patient marks a point corresponding to the intensity of his pain on a line, one end of which represents no pain and the other end, severe, incapacitating pain.
Contributors
Acute Low Back Problems Guideline Panel
Other Contributors
Project Directors
Consultants
Methodologists
Panel Staff
AHCPR Staff
Peer Reviewers
[1]
Pilot Reviewers
Attachment A. Algorithms
A1. Initial assessment of low back symptoms
A2. Treatment of acute low back problems on initial and followup visits
A3. Evaluation of the slow-to-recover patient limitations >4 weeks)
A4. Surgical considerations for patients with persistent sciatica
A5. Further care of acute low back problems
Attachment B. Pain Assessment Instruments
Attachment C. Patient Discussion Handouts
Four discussion handouts for
patients are provided. They are sufficiently specific to address a full range
of patient concerns. The patient's focus tends to change during treatment.
Early concerns may focus on comfort, or fear of potentially dangerous causes
of low back pain. Later, questions about special studies, procedures, and
diagnoses may arise. The few patients having trouble overcoming their activity
limitations may have to consider the relative benefits either of conditioning
more vigorously or of changing their activity goals. These handouts are not
intended to stand alone for all patients. Rather, they are designed to foster
the clinician's discussions with patients about important issues, as needed. The first discussion handout is intended to prepare the
patient for treatment recommendations. It can be provided to all patients if
no serious condition is detected (probably at the first visit). The
second discussion handout, which is only useful for the 10 percent of patients
who are slowest to recover, helps patients understand about the use of special
studies and the potential for diagnostic confusion. The third
discussion handout is for the same 10 percent of patients when they are facing
further treatment. It helps the patient understand the change in focus from
merely treating symptoms and avoiding debilitation to building activity
tolerance through safe exercises. The last discussion handout is only
for those patients who, for whatever reasons, are experiencing difficulties in
overcoming their activity limitations. It allows the clinician to help the
patient develop an understanding of available options. If the patient is
failing to overcome his or her limitations and seeks no other alternatives,
the clinician has an avenue to further address potential nonphysical (e.g.,
psychological and socioeconomic) pressures that can accompany activity
limitations due to low back symptoms. Your clinician has not found any dangerous causes for your back
problem. Almost everyone has a low back problem at some time. In only one
person out of 200 does the problem have a serious cause. A medical history and
physical examination alone are very good at detecting these uncommon cases. Nine out of 10 persons
with low back problems recover within 1 month, and most recover even sooner.
Therefore, an x-ray of your back or other tests at this time would only waste
your time. If your recovery happens to be slower than normal, your clinician
will then look further for a reason. Your clinician will suggest safe ways for you to be
more comfortable as you recover. But staying in bed is usually not the best
thing. More than a few days in bed actually weakens your back and could cause
your symptoms to last longer. Neither bed rest, medications, or any other
remedies should be expected to do away with all the discomfort. It is
important to be up and around as much as possible even if you are
uncomfortable. The sooner you return to normal daily activities, the sooner
your symptoms will disappear. Sitting may not be comfortable.
Sitting is not dangerous, but it puts more stress on the back than standing.
While recovering, try to spend less time sitting. To make sitting easier,
support the curve of your lower back with a towel or small pillow. If
possible, use a chair or other seat with a slightly reclining back. Keep anything you must lift close to the belly button.
Lifting a carton of milk or orange juice at arm's length can stress your back
more than lifting 30 pounds held close to the body. Also try not to bend
forward, twist, or reach when lifting. Your health care provider may suggest safe exercises
such as walking, swimming, or riding a stationary bike. If done correctly,
these exercises do not stress the back any more than does sitting on the side
of your bed (which is not dangerous). What exercising does is keep your back
muscles from becoming weakened by not enough activity. In addition, exercise
is good for your general health, can speed your recovery, and may help protect
you from future back problems. As your symptoms lessen, daily exercise will
make it easier for you to resume your normal activities. There is no hint of a serious problem. Your back symptoms are the kind that usually disappear within a month.
Expect a rapid recovery. No medications or other treatments, including
home remedies, can be expected to relieve all the discomfort immediately. You may need to change some daily activities to keep from irritating your
back. But stay active enough to keep from weakening your muscles. If
you are one of the few who is slow to recover, your clinician will look for
the reason. Even if you are slow to recover, there is little chance of a
serious reason for your back problem. If your back problem is slow to
recover, your health care provider may consider special studies (tests) to
find the reason. They may include blood tests; or an imaging study may be
needed to view your spine. Nerve tests may help identify certain leg
problems. The chances are good that your problem will not be serious. In only
one person out of 200 do low back problems have a serious cause. You may have read or heard
of tests like MRI, CAT scan, or myelogram. These are special imaging studies.
They use special equipment to provide different views of body structures like
your spine. You may wonder why your health care provider did not order these
tests in the first place. There is a good reason. Imaging studies can be
confusing. By themselves, they cannot tell the difference between possible
causes of a back problem and common changes in the spine because of aging. If your
back symptoms affect your legs and are not getting better, a herniated lumbar
disc (what many people call a slipped disc) may be the reason. The disc can
press on a nerve root in your back and can either irritate the nerve or affect
its function. If tests show strong evidence that this is happening, surgery to
take the pressure off of the nerve may speed your recovery. Medical science cannot always explain the
exact cause of most common low back symptoms. But medical science is very good
at finding out if you have a dangerous condition causing your symptoms. If
your problem is not caused by a serious condition, you can continue looking
forward to recovery. Remember to continue to exercise as you were instructed by your health care
provider and as described in Handout 1. It is important not to neglect your
muscles. Exercise regularly! Special studies are not needed for early detection and care of low back
problems. Special studies can mislead if used alone. They can give
additional information about a problem if used with other evidence. If your health care provider suggests surgery, ask what the evidence is for
surgery. Ask about your choices and what would happen without surgery. Get a
second opinion from another health care provider. Your surgeon will understand
how important it is for you to be sure. By now
your health care provider has given you the news that you can comfortably
begin to get back to your daily activities. Even if you required surgery, you
can now safely begin a specific, gentle exercise program to condition your
body and your back muscles. This program will increase your back's ability to
help you do the things you want and need to do. Trains the muscles that protect your back. Conditions your whole body. Stimulates the body to make its own powerful pain killers. Allows you to do more things more comfortably. Although your recovery seems slow, your
symptoms will continue to decrease unless you are inactive. However, your back
may never feel as young as it once did. This happens to many of us by age 30,
most by age 40, and just about everyone by age 50. Back problems often are the
first sign of aging. You may have noticed that few professional athletes can
continue competing beyond age 40. While some people may be able to resume
strenuous activity after back problems as they get older, it usually needs to
be at a slower pace. Most people need to shift gears and make changes in goals
and activities as they grow older. Even at a slower pace, exercise will help
you to be able to tolerate more of your daily activities. As you begin
to recover, the goal is to try to prevent back problems from returning or, if
they do return, being severe. Success will depend upon two factors. The first
is the condition of your protective muscles. The second is the activities you
ask your back to tolerate. Although exercises
such as walking, stationary bicycling, or swimming are safe, you may feel some
discomfort when you first start. After muscles become better conditioned, the
soreness goes away. For example, during the winter when the weather is bad and
many of us might stay indoors and be less active, the muscles of the back can
lose their conditioning. When the first day of spring arrives and many of us go
out to garden, the back may begin to ache when the out-of-condition protective
muscles easily tire. Continuing such work daily over a few days or weeks
reconditions the protective muscles so that they don't tire quite so easily,
and the soreness disappears. Regular activity is essential to obtain the conditioning
effect to protect your back. Conditioning is achieved by building up to 30
minutes of continuous walking, stationary cycling, or swimming at a targeted
heart rate (Table 1) or through jogging for 20 minutes. Conditioning works best if
combined with your normal, daily activities both at home and at work. Stay as
active as possible and exercise every day. Both your level of physical conditioning
and the stresses you put on your back will determine how often you will have
problems and how severe they become. Conditioning usually requires
daily work and commitment. Be sure your activity goal is realistic and
you know what it will take to achieve it. Once you are over your back
symptoms, or after a month of general conditioning training, your health care
provider may suggest that you begin doing back muscle, trunk, or extremity
exercises to gain further tolerance for specific tasks. If you have
great difficulty resuming your previous daily routine, you may need to
consider whether your old routine is realistic for you now. By now, your health care provider has made every effort to seek a
medical reason for your continued activity limitation. You are well into the
exercise program intended to condition your back for the activities you need
to do. Unfortunately, for some people success is less easy and slower to
achieve. If this is the case, there are many things to consider. Few middle-aged persons have a back that is as
strong as it was at age 18. Medical science presently cannot reverse the aging
process that limits activities requiring both speed and strength. Young people
may find it hard to accept these limitations. Older people commonly find it
difficult to give up or alter activities they have been doing for a long
time. Ask yourself three key questions about
your daily activity requirements:
Can a reasonable exercise program
overcome my back problem? Will it be possible to continue a more
time-consuming exercise program and my usual daily requirements long term? Is there any way I can change my activity requirements now or in the
future? Whether or not you explore job opportunities alone or with professional help,
remember this important point: Explanation of Handouts
C1. Handout 1: Back problems?
The news is good.
You should recover soon.
Even with back symptoms, you may
be able to continue your usual activities. But you might have to slow your
pace. Strenuous activity or heavy lifting could give you trouble. If you work
outside the home, much depends on the kind of work you do. Office work may
require few changes. On the other hand, if your job involves heavy
labor-like a furniture mover-you will probably have trouble
working as usual right away.
Age also makes a difference. As we age, so
do our spines. Activities that require speed and strength become harder to do.
This happens to many people by age 30, to most people by age 40, and to nearly
everyone by age 50. Consider your age as you plan your daily tasks when
recovering from a back problem. You can ease your discomfort safely.
You may need to make changes in your daily activities.
Lifting.
Exercising can help your back.
C2. Handout 2: Seeking a reason for slow recovery...
Special tests may be needed.
Why wait to do special studies?
As we grow older, the spine changes. Almost half the population has
aging changes in the spine as early as age 35. Yet most people who have such
changes will not have a back problem lasting longer than 1 month. Remember
that nine out of 10 people who have low back problems recover within 1 month.
For these persons, imaging studies are unnecessary and confusion can be
avoided. The tests could show a condition that is really not a problem and has
no connection to back symptoms.
Imaging studies are seldom used
alone. Surgery is never based on imaging studies alone. The studies could find
something that is not really the cause of your problem. Before deciding whether
imaging studies are needed, your health care provider should review your
physical examination carefully. He or she may also do other kinds of tests to
find evidence of a problem. Ask your health care provider to explain what tests
are needed for you.
Table 1 lists
a number of terms that are commonly used to describe (diagnose) the cause of
low back symptoms. However, scientific studies have not been able to show a
connection between these diagnoses and back symptoms. In addition, there is no
evidence that these conditions benefit from surgery or other specialized forms
of treatment. When is surgery a choice?
If your
health care provider tells you that surgery is a possibility, ask about your
choices. Ask what would happen without surgery. Before agreeing to surgery, get
a second opinion from another health care provider. Also, ask about the tests
that were done to suggest that surgery is the best approach for your back
symptoms. Table 2 lists some conditions or diagnoses that sometimes benefit from surgery or
other special treatment. Tests cannot always tell you the cause of your symptoms.
Exercise is important.
C3. Handout 3: Overcoming your back problem
Start with a simple,
safe exercise such as walking, stationary bicycling, or swimming to build your
general stamina. If you have been inactive, you may need to begin slowly and
gradually increase your activity each day. Your health care provider will make
specific recommendations for safe exercises that do not stress your back any
more than sitting on the side of your bed. Exercise helps because it:
You also will
find out what you can do easily and what takes more effort. Reality about back problems.
Once you
have had an activity-limiting back problem that lasts more than a few weeks,
there is a 40 to 60 percent chance of having another back problem within the
next few years. However, symptoms usually are not as severe in future episodes
as in the first episode. Success.
Ignoring either of these factors usually
means more back problems. For example, a coal miner can expect further problems
because mining is so demanding on the back. By contrast, a member of royalty
who never needs to stress his or her back but does no conditioning exercises
also can expect regular back problems. How well YOU do in the future will
depend on what kind of condition you are in and what you ask your back to do.
The more easily you and your protective muscles tire, the greater the chance
that your symptoms will return. Taking action to condition the protective
muscles of your back can reduce your future problems. Safe exercises that are good for you and your back.
Remember that an increase in discomfort in
an already painful back is common. But safe exercises (that involve less stress
on the back than sitting on the side of the bed) should not harm your back.
The shorter the time since beginning the conditioning, the greater the chance
of increased soreness. Conditioning requires regular activity.
Your health care provider
may have suggested ways to modify your daily chores to reduce the chance of
irritating your back. Such changes at home or work are usually temporary. They
are intended to give you time to improve the condition of your protective back
muscles so that you can resume most normal activities.
Table 2
offers guidelines to your health care provider on work recommendations to
allow you reasonable time to recondition your back. Long-term activity
tolerance varies greatly from person to person. Age and overall health are
important factors, too. Regular, mild exercise may be enough for some. Others
may be able to return to vigorous activities at a slower pace. C4. Handout 4: When exercise is not helping
Age is important.
Some people continue to look for a cure when progress is slow.
Such efforts rarely succeed. Consider a basketball star like Larry Bird. Money
was surely no object in seeking a cure for his back problem. He could afford
the most expensive medical care and conditioning programs. Nevertheless, he was
forced to retire at age 34. His back could no longer tolerate the physical
stress of basketball.
How many athletes in strenuous sports can compete
beyond age 35 or 40? Very few! Most of us must adjust our activities as we
age, regardless of occupation or level of physical conditioning, many by age
30, most by age 40, and just about all of us by age 50. Some people can
continue strenuous activities into their older years, especially if they are
able to do it at their own pace. Others may need to consider change. Be realistic.
If a reasonable exercise program is not helping you,
there are several options: (1) You can choose to put up with discomfort and
expect some setbacks. (2) You can begin a more time-consuming conditioning
program. (3) You can change the pace of doing difficult activities. This may
include a job change. People may use a combination of the three approaches.
Considering a job change is difficult, especially if back problems
continue to limit your ability to do your work. Again, ask yourself this
important question: "Is my activity goal realistic, or do I need to look at my
options?" A review now might help you avoid a similar dilemma in the near or
distant future, when increased age may work against you. Being a few years
older sometimes makes a big difference in the chance of changing jobs. Some
creative planning could benefit you now, or in the future, especially if your
job activities present a problem.
When considering a job or career
change, it is important to gather information from many sources. Some
possibilities include private career counselors, local or State employment
offices, and veterans' or consumer groups. You may also want to talk to someone
working in the field. Information is your ally.
[Tables]
Surgery is sometimes used to relieve the pressure on the nerve and can speed recovery if the diagnosis is based on strong evidence. Surgery should no be expected to make the back brand new. Spinal stenosis is an uncommon cause of walking limitation in the elderly. It is very rare under the age of 60. Surgery to take pressure off the nerves can improve walking distance and leg pain. Spondylolisthesis is measurable slippage of one vertebra upon another. In extremely rare cases, the slippage may be great enough to affect nerve root function. Surgery is sometimes used to take pressure off of the nerve and to fuse the vertebrae to prevent future slippage. Surgery is commonly used to repair a fracture or dislocation if the fracture or dislocation affects the spinal nerves If the condition is verified by a positive blood test and is not osteoarthritis or degenerative joint disease, nonsteroidal antiinflammatory drugs (NSAIDs), such as ibuprofen, may be used Try to maintain your daily activity as close to your normal level as possible. As soon as possible begin walking, riding a stationary bicycle, or swimming. Choose what works for you. Gradually build up to 30 minutes of activity without stopping. Once you can tolerate 30 minutes of activity, establish a target heart rate that will help you to condition your muscles, heart, and respiratory system. Then, your health care provider may also recommend some exercises for your back muscles Table 1. Estimated accuracy of medical history in diagnosis of spine disease causing low back problems
References Disease to be detected Medical history red flags True-positive rate (sensitivity) True-negative rate (specificity) Deyo and Diehl[26] Cancer Age >= 50 0.77 0.71 Previous cancer history 0.31 0.98 Unexplained weight loss 0.15 0.94 Failure to improve with 1 month of therapy 0.31 0.90 Bed rest no relief > 0.90 0.46 Duration of pain > 1 month 0.50 0.81 Age > 50 or history of cancer or unexplained weight loss or failure of conservative therapy 1.00 0.60 Waldvogel and Vasey[64] Spinal osteomyelitis Intravenous drug abuse, UTI, or skin infection 0.40 NA Unpublished data[a] Compression fracture Age >= 50 0.84 0.61 Age >= 70 0.22 0.96 Trauma 0.30 0.85 Corticosteroid use 0.06 0.995 Deyo and Tsui-wu[59], Spangfort[63] Herniated disc Sciatica 0.95 0.88 Turner, Ersek, Herron, et al.[66] Spinal stenosis Pseudoclaudication 0.60 NA Age >= 50 0.90 [b] 0.70 Gran[60] Ankylosing spondylitis Positive responses 4 out of 5 0.23 0.82 Age at onset <= 40 1.00 0.07 Pain not relieved in supine position 0.80 0.49 Morning back stiffness 0.64 0.59 Duration of pain >3 months 0.17 0.54
a. From 833 patients with back pain at walk-in clinic as reported in
Deyo, Rainville, and Kent[54]. All received plain lumbar
roentgenograms.
b. Author's estimate. Table 2. Estimated accuracy of physical examination for lumbar disc herniation among patients with sciatica
References Test True-positive rate (sensitivity) True-negative rate (specificity) Comments Hakelius and Hindmarsh[61]; Kosteljanetz, Espersen, Halaburt, et al.[37] Ipsilateral SLR 0.80 0.40 Positive result: leg pain at < 60 degrees Hakelius and Hindmarsh[61]; Spangfort[63] Crossed SLR 0.25 0.90 Positive result: reproduction of contralateral pain Hakelius and Hindmarsh[61]; Spangfort[63] Ankle dorsiflexion weakness 0.35 0.70 HNP usually at L4-L5 (80 degrees) Hakelius and Hindmarsh[61]; Kortelainen, Puranen, Koivisto, et al.[35] Great toe extensor weakness 0.50 0.70 HNP usually at L5-S1 (60 degrees) or L4-L5 (30 degrees) Hakelius and Hindmarsh[61]; Spangfort[63] Impaired ankle reflex 0.50 0.60 HNP usually at L5-S1; absent reflex increases specificity Kortelainen, Puranen, Koivisto, et al.[35]; Espersen, Halaburt, et al.[37] Sensory loss 0.50 0.50 Area of loss poor predictor of HNP level Aronson and Dunsmore[56] Patellar reflex 0.50 NA For upper lumbar HNP only Hakelius and Hindmarsh[61] Ankle plantar flexion weakness 0.06 0.95 Hakelius and Hindmarsh[61] Quadriceps weakness < 0.01 0.99
Values represent rounded averages where multiple references were available.
All results are from surgical case series.
HNP = herniated nucleus pulposous.
SLR = straight leg raising. Handout C2: Table 1. Common diagnosis used to explain back symptoms
Annular tear Adult spondylolysis Myofascitis Fibromyalgia Disc syndrome Strain Spondylolysis Lumbar disc disease Facet syndrome Degenerative joint disease Sprain Osteoarthritis of the spine Disc derangement/disruption Dislocation Subluxation Handout C2: Table 2. Diagnoses that may benefit from surgery or other treatment
"Leg pain due to herniated lumbar disc". "Leg pain due to spinal stenosis." "Leg pain with spondylolisthesis." "Fracture or dislocation." "Spinal arthritis." Handout C3: Table 1. Building exercise tolerance
Handout C3: Table 4. Guidelines for sitting and unassisted lifting
Symptoms Severe Moderate Mild None Sitting[1] 20 min 50 min. Unassisted lifting[2] Men 20 lbs 20 lbs 60 lbs 80 lbs Women 20 lbs 20 lbs 35 lbs 40 lbs Figure. Panel ratings of available evidence supporting guideline statements.
* Met minimal formal criteria for scientific methodology and relevance to population and specific method addressed in guideline statement.A = Strong research-based evidence (multiple relevant and high-quality scientific studies).
B = Moderate research-based evidence (one relevant high-quality scientific study or multiple adequate scientific studies*).
C = Limited research-based evidence (at least one adequate scientific study* in patients with low back pain).
D = Panel interpretation of information that did not meet inclusion criteria as research-based evidence.