“Leg length discrepancy” (LLD) of as little as 1.5 centimeters can affect
walking ability. LLD may be “anatomical,” meaning there is a measured
difference in the length of the leg bones or a difference in the structure of the hip,
knee, or ankle joints. Otherwise, there may be a “functional” cause (one leg
looks longer than the other due to an imbalance in the muscles, tendons, and
ligaments of the hip and leg). Although the most common treatment for LLD
involves placing a lift in the shoe of the shorter leg, this might actually make
symptoms worse in those with a functional problem by allowing muscular
imbalances to become more pronounced. Functional LLD may be better treated
by physical therapy.
P.S. Functional leg length discrepancy’s primary cause is chronically contracted
muscles. Tightened waist and lower-back muscles can laterally tilt the pelvis,
while tight gluteal muscles and hip rotators can cause one leg to appear to be
longer than the other.