Topics In Clinical Chiropractic 1996; 3 (4): 32–35 ~ FULL TEXT
Peter D. Aker, MSc, DC, FCCS(C), FCCRS(C) and Johanne Martel, BSc, DC
Division of Graduate Studies and Research,
Canadian Memorial Chiropractic College,
Purpose: Complementary and alternative medicine strategies often offer patients more holistic approaches to health care than traditional disease-specific allopathic models. Chiropractic has historically offered a similar approach to improved health through the use of regular spinal manipulation or adjustments, often termed maintenance care. There is strong anecdotal support of regular spinal manipulation, both from chiropractors and their patients that invites further research to substantiate these claims.
Method: A qualitative review of relevant literature was undertaken.
Summary: There is no scientific evidence to support the claim that maintenance care improves health status. Before a large-scale, multi-centered clinical trial can be pursued, a series of preliminary studies need to be conducted to delineate the parameters of care to be used in the clinical trial, the outcome measures to be used, and the feasibility of conducting such a complicated and resource-intensive study.
Key words: alternative medicine, chiropractic, holistic health, manipulation (orthopaedic), preventive health services, research design, spine
From the Full-Text Article:
One recent change observed in health care delivery has been a shift from a disease-oriented, physician-controlled perspective to a wellness, preventive, and patient-centered perspective. Many individuals are turning toward complementary and alternative medicine strategies for more holistic approaches to their health care.  Chiropractic care, with its health-oriented philosophical basis and its nonsurgical and drug-free methods, is considered by many to be one of the most frequently sought alternative health care approaches.
Certain groups inside and outside the profession argue that
chiropractic is neither an alternative to, nor a complement of
traditional medicine, but rather a viable mainstream approach.
Recent summary evidence supporting the use of manipulation
for low back pain,  neck pain, [3, 4] and headache  may help to
place chiropractors at par with other mainstream health care
providers. This possibility seems more likely when one considers that most patients (about 96%) see chiropractors for
musculoskeletal complaints.  However, the view that the
potential benefits of chiropractic are limited to certain musculoskeletal disorders is not shared by all, and many chiropractors consider their treatments to be a valuable component of a general health care regimen. [69, 7] There is ample evidence that
chiropractors can incorporate effective clinical preventive
services into their practice. [8, 9] It is not clear, however, whether
chiropractic care consisting only of spinal manipulation or
adjustments will increase wellness or improve global health.
Consequently, when delivered for the purposes of general
wellness or global health, spinal manipulation remains an
alternative or complementary form of care.
The objective of this article is to review the literature and
describe the rationale behind the use of maintenance care,
which is often described as care used to improve or maintain
general health status. A line of investigation leading to a larger
clinical trial on the effects of maintenance care is proposed.
Since its inception, a basic tenet of the chiropractic profession has been holism.  Even today, many chiropractors adhere to the opinion that chiropractic care maintains or improves general health. This model of health care originated in
the late 1800s, when DD Palmer described the first chiropractic treatment and proposed a natural approach to improve
health and rid the body of disease. Its initial postulate was that
the correction of spinal misalignments by manipulation (chiropractic adjustment) would remove nerve interference. Removal of nerve interference would restore patients' vital nerve
and energy flow, which in turn would improve the innate self-healing capacity. [11, 12]
The historical concepts of "bones out of place" and "nerve
interference" have since been challenged and in some cases
replaced with a multitude of alternative hypotheses regarding
the mechanisms of spinal manipulation. These include theo-
ries on segmental dysfunction,  somatoautonomic reflexes, 
plasma beta-endorphin levels,  and other systemic effects. 
More recently, it has been suggested that many of these
hypotheses may need to be conjoined to explain the effects of
spinal manipulation.  There is, however, only sparse basic
science research to support these hypotheses.
Evidence that manipulation reduces pain and improves
range of motion has been uncovered in both basic science and
clinical research. [2, 3, 18, 19]
Other postulated effects remain unsubstantiated clinically, although evidence from animal studies
lends some support.  Without the basic science research to
substantiate their theories, chiropractors have had to resort to
clinical observation to support their claims for improved
health through regular chiropractic care. Many chiropractors
believe in the inherent capacity of the body to heal itself and
in the power of spinal manipulation to enhance the healing
process. [21, 22] Their beliefs, however, are based on historical
teachings and clinical observations, not on scientific evidence, The fact that many chiropractors have these beliefs,
apply them in clinical practice, and promote them in their
educational systems is sufficient reason to study them thoroughly and rationally.
Chiropractors are often chastised for focusing on mainte-
nance care through spinal adjustment by critics from inside
and outside of the profession. Those opposed to this style of
practice state that there is no supporting evidence. Using
"evidence" to support practice patterns is, however, a rela-
tively new concept in health care. It has been estimated that
only about 15% of the procedures used in mainstream medical
practice have been studied using sound scientific methods. 
Even in situations where randomized trials have provided
good evidence of effectiveness, physicians are reluctant to
change their practice patterns, [24, 25] and a considerable time lag
occurs before change is seen.  "Absence of evidence is not
evidence of absence."  It is not uncommon for reasonable
patient care to be delivered in spite of the absence of evidence
of effectiveness. In these circumstances, clinicians must use
common sense and weigh factors such as patient safety, cost,
and past experience in their decision making.
Research in and of the chiropractic profession is relati vel y
young. Thus, it is not surprising that chiropractic lags behind
medicine in terms of establishing practice patterns based on
scientific methods. Since initiatives for research often stem
from clinical observations, it behooves the chiropractic pro-
fession to allocate 'resources to study those theories that have
been proposed by clinicians to be potentially viable alterna-
tive forms of health care.
Existing literature regarding maintenance care is sparse and
at best anecdotal. There is no clear understanding of its use or
even of its definition. Definitions for preventive/maintenance
care have been provided in Canada through the Clinical
Guidelinesfor Chiropractic Practice in Canada  (Glenerin)
and in the US through the Guidelines for Chiropractic Quality
Assurance and Practice Parameters  (Mercy Conference).
The Glenerin Guidelines define preventive/maintenance care as:
elective care given at regular intervals designed to maintain maximum health and promote optimal function. It may incorporate
screening procedures designed to identify developing risk problems
pertaining to the patient's health status and give advice on same.
 (p. 193)
The guidelines also point out that preventive/maintenance
care is discretionary and elective; must include periodic
reassessment; may include treatment, education, and counseling; and generally should be delivered at a frequency of not
more than once per month.
The Mercy Guidelines define preventive/maintenance care as:
any management plan that seeks to prevent disease, prolong life, promote health, and enhance the quality of life. A specific regimen is designed to provide for the patient's well-being or for maintaining
the optimum state of health.
 (p. 181)
These guidelines also describe preventive/maintenance care as
discretionary and elective and as consisting of the use of chiro-
practic adjustments, health screening, health promotion, and
wellness care. Both sets of guidelines clearly distinguish main-
tenance care from supportive care. Similar guidelines are cur-
rently being formulated for chiropractic practice in Australia.
In general, support for the use of maintenance care in both
of these guidelines was not based on published material but
rather on collective opinion regarding close to 100 years of
chiropractic practice. Patients often describe global health
improvements and satisfaction while utilizing maintenance
care. Studies have been conducted that describe the use of
maintenance care in clinical practice. [30-33] The results indicate
that between 79% and 98% of chiropractors support such care.
Definitions of maintenance care were not made available in
these studies, and doctors were free to interpret this concept
using their own background or bias. Methodologically weak
questionnaire design and sampling also limit the usefulness of
these studies, but they represent the best available information
on the subject. In one investigation, 86% of respondents
regarded spinal manipulation as their best tool for health
promotion and maintenance, and 92% believed that it pro-
moted health in asymptomatic patients. 
The specific health benefits of maintenance care, in particu-
lar the use of spinal manipulation, were not reported. Many
authors claim that chiropractors have a role in health promo-
tion, but typically this role is attributed to patient education
and advice rather than to spinal manipulation. [30, 33-37] There is
no scientifically valid research to support the assumption that
spinal manipulation alone is a viable health promotion strat-
egy. [31, 37-39] The report Chiropractic in New Zealand states that
there is "no basis for recommending that any health benefit be
payable in respect of preventative chiropractic."  (p. 47)
LINE OF INVESTIGATION
Overall, there is a tremendous need to research the hypoth-
esis that regular maintenance chiropractic care (spinal ma-
nipulation) will improve an individual's health status. The
most robust type of investigation for this question would be a randomized, controlled, clinical trial or a prospective concur-
rent cohort study. However, these complicated studies cannot
be embarked on until preliminary studies are performed.
Below are the key tasks our study team has identified as
needing to be accomplished prior to conducting a larger scale
clinical study (see also Table 1).
Table 1: Structured line of investigation for researching
Operationally define maintenance care.
Determine best method for measuring health status.
Pretest operational definitions and outcome measures.
Design and run controlled clinical trial.
Step 1: Operationally define maintenance care
Develop a questionnaire to define maintenance care (its
patterns of use and expectations of use) using formal
consensus and validity processes.
Test the questionnaire forreliability using a subsample of
Once validity and reliability have been established, dis-
tribute the questionnaire to a randomly selected represen-
tative sample of practicing chiropractors.
Step 2: Determine best method for measuring health status
Perform a literature review of health status instruments to
determine if there is an existing global health status
instrument with good measurement properties that could
measure both positive and negative health attributes (not
simply disease or disability).
Acquire a licensing agreement to use an identified health
status measurement instrument or design and pretest a
new instrument to measure expected positive health
attributes identified by chiropractors in step 1.
Step 3: Pretest operational definitions and outcome measures
Perform a small-scale clinical study using treatment
parameters defined by the survey in step 1 and the health
status outcome measures identified in step 2.
Identify potential problems and develop strategies to
overcome them in the implementation of a larger scale
study. Feasibility issues to consider include sample size
estimation, compliance, costs, and viability.
Step 4: Design and run controlled clinical trial
Identify a suitable control group.
Initiate long-term, multicenter controlled clinical trial by
randomly assigning (or allocating, in cohort design)
subjects to receive or not receive maintenance care.
Maintenance care has been used in chiropractic for just over
100 years. Numerous anecdote-based claims regarding health
benefits derivable from maintenance care have been made by
practitioners and patients. Due to cost constraints imposed
upon the health care industry in recent years, governments, patients, and other payers are less willing to pay for treatments
that have not been shown (through scientific methods) to be
effective. The burden of proof is now on all health professions
to establish which forms of care help patients more effectively
and efficiently than others. Considering the widespread use
and acceptance of maintenance care in chiropractic practice
and its potential health benefits, the profession (and its advo-
cates) must create the necessary resources to develop studies
on its effectiveness. Without these studies, the profession is at
risk of having this form of care denied by third-party payers.
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