March
2003
Orthotic support for low back
pain
by Dr. Mark N. Charrette
Whenever
we stand, walk, or run, the lumbar spine and pelvis balance on the lower
extremities. If leg length inequalities, foot asymmetries, or postural
misalignments exist, abnormal forces traveling along the closed kinetic
chain are likely to interfere with spinal function. [1]
Most
chronic low back pain is due to some form of musculoskeletal weakness or
failure. [2] A major cause of chronic lumbar spine breakdown is
microtrauma, which is produced by the following conditions: biomechanical
errors; excessive external loads; structural asymmetries; or tissue
weaknesses. The source of these conditions, which is often an
imbalance/condition in one or both of the feet, must be recognized and
treated in order to prevent further breakdown and chronic damage.
Foot
conditions
The
feet make up the body's postural foundation. Statistical evidence shows
that at birth, most people have perfect feet. By age 20, 80% of humans
have developed some type of problem, and by age 40, nearly everyone has
some kind of foot condition. Many foot problems eventually contribute to
health concerns farther up the kinetic chain, especially generalized back
pain conditions. It's in the best interest of both the doctor and patient,
therefore, to be able to identify a potential low back problem before it
is allowed to affect a patient's health and/or lifestyle.
Support
with orthotics
A
major factor in reducing excessive forces on the lumbar spine is
frequently overlooked by healthcare professionals: the use of external
supports (orthotics, heel lifts) to decrease external forces. The
following are commonly seen conditions in which the lower extremity can
have a major impact on lumbar spine function. In each of these situations,
custom-made orthotics are not only appropriate, they will contribute
significantly to a cost-effective treatment outcome:
***
If a patient presents with excessive foot pronation and/or arch
collapse, a torque force will produce internal rotation stresses to the
leg, hip, pelvis, and low back. [3] The result is recurring subluxations
and eventual ligament instability affecting the sacroiliac and lumbar
spine joints. These forces can be decreased significantly with the use of
flexible, custom-made orthotics. [4]
***
In cases of degenerative changes in the lumbar discs and facets,
external heel-strike force may aggravate and perpetuate low back pain.
This force is easily reduced with the use of shock-absorbing shoe inserts
[5] or orthotics which contain viscoelastic compounds. Symptom reduction
is often dramatic.
***
An anatomical difference in leg length produces strains to the
pelvic and low back structures. These strains can cause not only chronic
pain, [6,7] but have also been shown to result in specific degenerative
changes. [8] The use of lifts and orthotics has been shown to reduce these
structural strains and bring about significant response. [9] In fact, a
15.5 mm leg length inequality in a patient can be reduced to just 4 mm
with the use of a custom-made, flexible orthotic. [10]
Look
to the feet
Getting
the answers a few simple questions (see below) can provide valuable
insight into the cause(s) of many of your patients' back pains. When the
back acts up, check the feet!
1.
Do you stand or walk on hard surfaces for more than 4 hours a day?
2.
Do you participate regularly in any physical sport (basketball, baseball,
tennis, golf, bowling, etc.)?
3.
Are you age 40 or over?
4.
Have you ever had a prior injury to your knee, back, or neck?
5.
Do your shoes wear unevenly?
6.
Do you have joint pain while standing, walking, or running?
7.
Is one of your legs shorter than the other?
8.
Do you have knock-knees or bow legs?
9.
Do you have any obvious foot problems (bunions, corns, flat feet, etc.)?
10.
Do your feet "toe out" when you're walking?
If
your patient gives an affirmative answer to any of the above, consider him
or her a likely candidate for flexible, custom-made orthotics.
References
1.
Keane GP. "Back pain complicated by an associated disability."
In: White AH,
Anderson
R.
eds. "Conservative Care of Low Back Pain."
Baltimore
:
Williams & Wilkins, 1991:307.
2.
Fulton
M.
"Lower back pain: new protocols for diagnosis and treatment." Rehab
Management 1988; Nov/Dec:39-42.
3.
Hammer WI. "Hyperpronation: causes and effects." Chiro Sports
Med 1992; 6:97-101.
4.
Dananberg HJ, Giuliani M. "Chronic low-back pain and its response to
custom-made foot orthoses." J Am Podiatr Med Assoc 1999;
89:109-117.
5.
Light LH, et al. "Skeletal transients on heel strike in normal
walking with different footwear." J Biomechanics 1980;
13:477-480.
6.
Giles LGF, Taylor JR. "Low-back pain associated with leg length
inequality." Spine 1981; 6:510-521.
7.
Friberg O. "Clinical symptoms and biomechanics of lumbar spine and
hip joint in leg length inequality." Spine 1983; 8:643-651.
8.
Giles LGF, Taylor JR. "Lumbar spine structural changes associated
with leg length inequality." Spine 1982; 7:159-162.
9.
Hoffman KS, Hoffman LL. "Effects of adding sacral base leveling to
osteopathic manipulative treatment of back pain: a pilot study." JAOA
1994; 94:217-226.
10.
Yochum TR, Barry MS. "The short leg" (revised edition).
Practical Research Studies 1994; 4(5).
(Dr.
Mark N. Charrette is a 1980 summa cum laude graduate of
Palmer
College
of Chiropractic. Over the past 15 years he has lectured extensively on
spinal and extremity adjusting throughout the
U.S.
,
Europe
,
the
Far
East
,
and
Australia
.
He received a Bachelor's degree from
Illinois
State
University
(summa cum laude) in 1976, where he was an NCAA All-American in 1974. Dr.
Charrette is a featured speaker in Foot Levelers' 2003 Spring Seminar
Series )
