Clinical Trial Details
— Status: Completed
Administrative data
| NCT number |
NCT01097109 |
| Other study ID # |
02171013Exp. |
| Secondary ID |
|
| Status |
Completed |
| Phase |
N/A
|
| First received |
March 30, 2010 |
| Last updated |
April 21, 2012 |
| Start date |
March 2010 |
| Est. completion date |
May 2010 |
Study information
| Verified date |
April 2012 |
| Source |
Nova Southeastern University |
| Contact |
n/a |
| Is FDA regulated |
No |
| Health authority |
United States: Institutional Review Board |
| Study type |
Observational
|
Clinical Trial Summary
The study aims to determine if somatic dysfunctions of the pelvis, sacrum and lower lumbar
spine have an effect on weight bearing. Our subjects are young, healthy subjects without
recent soft tissue or osseous injury, a less than predetermined leg length discrepancy or
OMM/chiropractic treatment. Their leg lengths will be measured; weight-bearing will be
measured using a specialized scale and somatic dysfunctions diagnosed to determine if any
correlation exists.
Description:
Most sources claim that in individuals with leg length discrepancies, they tend to place
more weight through the shorter lower extremity.1,2 Few cases state that the opposite is
true.3 Many health care practitioners diagnose leg length discrepancies. Osteopathic
physicians who practice with Osteopathic Manipulative Medicine (OMM) will also diagnose leg
length discrepancies. They use testing to evaluate whether a leg length discrepancy is
structural or functional. A structural leg length discrepancy is associated with shortening
of bony structures.4 The structures affected can be due to congenital defects, which result
in possible structural shortening of the tibia or femur, slipped capital femoral epiphyses
(SCFE), or congenital dislocation. Other causes of structural leg length discrepancies
include post total hip replacement, infections, tumors, paralysis, and trauma, including
fractures where the gross length of a limb is altered.4 A structural leg length discrepancy
can be most accurately assessed by physically measuring the distance between the anterior
superior iliac spine (ASIS) and medial malleolus.4 The most reliable method of diagnosing a
structural short leg is through full body radiographs. 6 A functional leg length discrepancy
is a result of altered mechanics of the lower extremities. It is thought that a functional
short leg occurs secondarily to a rotated pelvis caused by joint contractures and/or axial
misalignments, including scoliosis.4 In osteopathic literature; functional leg length
discrepancies are also thought to be the result of altered positions of the pelvis and
sacrum. It is also thought in osteopathic philosophy that the position of the fifth lumbar
vertebra affects the position of the sacrum. Therefore dysfunction of L5 will change the
position of the sacrum such that a functional short leg is created.2(p.780-782) A common
cause of functional leg length discrepancies diagnosed by osteopathic physicians is that of
sacral base unleveling.5 The way in which a leg length discrepancy causes unleveling of the
sacrum is through the femoral head of the longer leg driving the pelvis into a posterior
rotation via forces placed through acetabular contact. Then the pelvis will typically rotate
forward in attempts to lengthen the shorter leg, causing the sacral base to become unlevel.5
In addition, the sacral base tilts toward the side of the short leg.6 Standing postural
x-rays, which outline sacral declination, are often used by chiropractors and osteopathic
physicians to diagnose functional leg length discrepancies.6 Another way that functional leg
length discrepancies are confirmed is through the supine to long sitting test, which tests
for the presence of innominate rotations that may affect leg length as the cause.
There is no research known to support the presence of somatic dysfunctions, leg length
discrepancies and altered weight bearing through lower extremities secondary to this.
It is common practice among osteopathic physicians who utilize OMM to diagnose
musculoskeletal somatic dysfunctions of the pelvis, sacrum and lumbar spine. All these
findings can contribute to low back pain. Therefore, it is the common practice of these
physicians to diagnose leg length discrepancies, as it may ultimately result in low back
pain.
Somatic dysfunction in osteopathic nomenclature is defined as 'impaired or altered function
of related components of the somatic (body framework) system: Skeletal, arthrodial and
Myofascial structures, and related vascular, lymphatic and neural elements'.2
There are specific somatic dysfunctions that lead to leg length differences. These effects
include the sacral base tilting toward the side of the short leg, a low iliac crest on the
short leg side, a forward rotation of the innominate on the shorter side and/or a posterior
rotation of the innominate on the side of the longer leg as a compensatory measure. The
lumbar spine will develop a convexity toward the side of the short leg.6 Their definitions
are as follows:
Anteriorly rotated innominate: Entire innominate appears to be rotated anterior in relation
to the opposite innominate. The ASIS will be more inferior or caudad and PSIS will be more
superior or cephalad.2(776-778), 6 Posteriorly rotated innominate: Entire innominate appears
to be rotated posterior in relation to the opposite hip bone. The ASIS will be more superior
or cephalad and the PSIS more inferior or caudad.2(776-778), 6 Superior shear of the
innominate: ASIS, PSIS and pubic ramus is more superior or cephalad than the opposite
side.2(776-778), 6 Inferior shear of the innominate: ASIS, PSIS and pubic ramus is more
inferior or caudad than the opposite side.2(776-778), 6
The way that osteopathic physicians determine the side of the somatic dysfunction is through
the ASIS compression test. This is defined as follows:
ASIS compression test: Test for lateralization of somatic dysfunction of the sacrum,
innominate or pubic symphysis. A posterior compression normally produces a palpatory sense
of 'give' or 'resilience' as the innominate glides slightly posterior at the sacroiliac
joint on that side. Somatic dysfunction of the pelvis on the side of compression produces
resistance to the test determining the side of lateralization which is analogous to the
determining the dysfunctional side. This is interpreted as a positive ASIS compression
test.2(777) Individuals who have suffered from any type of osseous or soft tissue traumatic
injuries in the last three months do not make suitable subjects for an evaluation of somatic
dysfunctions' effects on weight bearing. Neither do individuals who have suffered from any
type of osseous or soft tissue injuries in the lower extremity joints (knee, ankle, hip) in
the last twelve months. As stated earlier, leg length discrepancies may be a result of
trauma. Individuals who have suffered traumatic injuries within the last three months may
exhibit antalgic or compensatory postures which may displace weight bearing more through one
lower extremity than the other.7 This will ensure that the treatment population will be as
homogenous as possible and will improve reliability of the study.
Individuals who have suffered lower extremity injuries in the last twelve months may also
exhibit altered weight bearing distribution through the lower extremities. This may be
something, depending on the chronicity of the problem, which alters weight bearing for an
extended period of time which may vary depending on the person.7 Therefore, excluding
individuals who have suffered lower extremity trauma in the last twelve months will also be
excluded from the study to allow for more homogenous characteristics of our sample
population. The time constraints of three and twelve months respectively were deemed as the
exclusion times purely from anecdotal and clinical experience with lower extremity injury
from the principal investigator and his colleagues.
1. White, S.C., Gilchrist, L.A., Wilk, B.E. Asymmetric limb loading with true or simulated
leg-length differences. Clinical Orthopedics and Related Research, 2004,421,287-292
2. Ward, R. Foundations for Osteopathic Medicine 2nd Edition. 2003, p. 614-618, 780
3. McCaw, S.T., Bates, B.T. Biomechanical implications of mild leg length inequality.
British Journal of Sports Medicine, 1991, 25,10-13
4. Gurney, B. Review: Leg length discrepancy. Gait and Posture. 2002, 15,195-206
5. Dott, G.A., Hart, C.L., McKay, C. Predictability of sacral base levelness based on
iliac crest measurements. JAOA, 1994,4, 383-390.
6. DiGiovanna, EL. Schiowitz S. An Osteopathic Approach to Diagnosis and Treatment.
Philadelphia: Lippincott-Raven, 301.
7. Riegger-Krugh, C & Keysor, J.J. Skeletal malalignments of the lower quarter: Correlated
and compensatory motions and postures. J. Orthop Sports Phys Ther. 1996;23(2):164-170.
