BASIC PHYSIOLOGIC REACTIONS TO CHRONIC POSTURAL FAULTS
An injured person rarely resembles the textbook stereotype. No two people
react in an identical manner to actual or potential loss of body
balance. All vary somewhat in the accommodation process according
to one's structural and functional needs, the momentary potential
for redistributing body mass, and the visual efficiency necessary
to guide correct adjustments. Isolated muscle weakness should be
suspected especially in situations of head or pelvic tilt, trunk
imbalance, scoliosis, and uneven gait or limp.
Tolerance. Poor weight-bearing because of disease,
noxious reflexes, or just habit results in constant structural
malalignment allowing a disproportionate amount of weight and
muscle pull to be carried by some parts and not others. This
alters the normal locomotion apparatus and functions of the
internal organs as well. While these changes may develop
insidiously, the resulting static abnormalities progress to
pathologic changes in the body during standing, sitting, lying,
and motion. They have a distinct effect on physical performance.
They are tolerated for a short time, but sooner or later,
serious, often subtle, maladjustments result when the body's
resources for compensation become exhausted. These factors total
to predispose an individual to injury or hinder performance.
Endurance. An important factor in health care is that,
with good postural body mechanics, balance is maintained with the
least amount of muscular effort, thus encouraging longer
endurance, with less strain on any one part. Locomotion can be
made without wasted time or energy. Muscle pull in sustaining an
erect carriage is more direct, thus avoiding strain. A natural
balance is maintained between the iliopsoas group and the hip
extensors, and a similar condition exists at the knee and ankle
Effort. Energy requirements vary considerably with
different postures. The rigid "military" posture requires about
20% more energy than the relaxed standing posture. In the rigid
posture, blood pressure rises because of the muscle effort
required. A completely relaxed standing position requires little
more energy than that required for the sitting position.
Regional Effects. Postural faults can lead to a number
of regional disorders. For example, a round-shouldered posture
alters the glenohumeral articulating mechanism by depressing the
overhanging acromion in front and rotating the dependent arm
internally. Both of these conditions encourage cuff entrapment
and attrition. Exaggerated cervical or lumbar lordosis decreases
the size of the intervertebral foramina, frequently resulting in
chronic radiculitis and degenerative changes. An exaggerated
thoracic kyphosis decreases rib excursion and alters the
functional motion of the shoulder girdle.
In spinal imbalance, there always appears to be some degree of
intervertebral foramina insult present. Neuralgic pains in the
thorax and legs are common. Less common, because it mimics
visceral disease, is intercostal neuralgia. If originating in the
cervical region and associated with hypertrophic changes, pain is
often referred about the shoulders and down the arms, frequently
being mistaken for angina pectoris. Similar neuralgic pains in
the chest walls can be mistaken for pleurisy, pleural adhesions,
or pulmonary lesions. Auscultation will serve in the
A muscle in spasm or under strain from any cause (or an overstressed tendon
or ligament) will become congested. This congestion always
results in some degree of transudation and the conversion of
fibrinogen into fibrin, which acts as a cobweb-like adhesion or
interfascicular gluing that impedes fascial glide. As a result in
muscles, tendons, and ligaments under strain, painful
interfascicular constrictions occur, leading to the common algias
associated with these structures.
Trigger Point Development
When vascularized tissue is subject to strain, changes take place with
an invasion process resulting in possible fibrosis and calcific
tendinitis or syndesmitis. Events occur in the myofascial planes
at a point of major tensile stress leading to the development of
"trigger points" and the resulting delta or spread effect.
Muscles have their fascial encasements (epimesium, perimesium,
endomesium); and, because muscles lie and move on others, the
myofascial planes are described. The amount of fasciculi involved
in the all-or-none contraction effort determines muscle tone and
strength of muscle contraction. Furthermore, a muscle usually
does more work at one point of its composite than at another.
Circulatory disturbances are rarely absent in gross postural faults. A low
diaphragm results in venous congestion in its failure to assist
blood returning to the heart. Sagging viscera stretch mesenteric
vessels and narrow their lumina. Thus, circulatory symptoms may
manifest throughout the body. For instance, medical researchers
have recorded the relief of eyestrain and mild myopia in children
by postural correction alone. They explain this as a relief of
venous congestion in the head.
In extreme cases, impaired circulatory inefficiency may be
sufficient to produce a marked fall in blood pressure and loss of
consciousness. This is said to be the result of general muscle
relaxation with pooling of blood in the venous reservoirs,
especially in the abdomen, thus reducing the practical blood
volume. More often it causes only dyspnea and weakness, sometimes
accompanied by palpitation. Precordial pain resembling angina
pectoris is sometimes associated.
Faulty postural mechanics may cause the liver to rotate anteriorly and
to the right. Traction is thereby exerted on the common duct and
in some cases seriously interferes with biliary drainage. Ptosis
of the kidneys, especially the left kidney, results in traction
on the renal veins that may obstruct venous outflow to the point
of causing passive congestion and albuminuria.
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