SHORT LEG SYNDROME (UNEQUAL LIMB LENGTH) Biomechanics of the Short Limb

The presence of leg length discrepancy is usually associated with pelvic or lumbar misalignment. The short limb may be FUNCTIONAL, ANATOMICAL, or a COMBO of both. Studies have found that the majority of patients presenting to our offices are functional, but a growing number seen are anatomical, the result of post hip or knee replacement surgeries. Many of these can be corrected within shoe heel lifts. You need an understanding of unequal limb length biomechanics before prescribing a heel lift from Atlas Biomechanics.

FUNCTIONAL SHORT Limb:
1. The sacroiliac joint that is misaligned causing the sacral base to drop to one side.
2. Flexion or Extension with one of the iliac bones out of its normal anatomical position.
3. Posterior Tibial Tendon Dysfunction causing the subtalar joint to overpronate, effectively shorting the limb.

ANATOMICAL SHORT Limb:
1. Hip or knee replacement surgery.
2. Polio.
3. Congenital, birth injuries and infections to the growth plates.
4. Fractures.

BIOMECHANICS OF THE SHORT Leg:
1. Supination of the subtalar joint.
2. External rotation of the tibia.
3. External rotation of the knee.
4. Abnormal patella tracking.
5. Pelvic Tilt.
6. Shifting of the center of gravity to the short side.

BIOMECHANICS OF THE LONG LIMB:
1. Pronation of the subtalar joint.
2. Internal rotation of the tibia and the knee.
3. Abnormal patella tracking.
4. Vaulting over the hip joint.

GAIT EVALUATION OF THE UNEQUAL LIMB LENGTH:
1. Center of gravity shifted to the short side.
2. Unilateral early heel lift.
3. Pelvic Tilt.
4. Shoulder drop.
5. Unilateral subtalar pronation.
6. Unilateral shoe wear (lateral heel).
7. Abnormal knee rotation and patella tracking.

Atlas Biomechanics produces all of our heel lifts in the USA.

Shoe Heel Lifts come in small, medium and large. They are manufactured from either EVA/Rubber or Cork/Rubber blend.

Heights are:
1/8 inch (3 mm) heel lift 
1/4 inch (6 mm) heel lift   
3/8 inch (9 mm) heel lift 
1/2 inch (12 mm) heel lift 
and
Adjustable Heel Lift with Built-in Heel Wedge  

Teri Green
Atlas Biomechanics