In cases of hip dysplasia or a shortened femur, how is the involved leg's tibia positioned in relation to the uninvolved side?

• A. Ahead of
• B. Behind
• C. Equal to
• D. Higher than

Answer: (B)

In cases of hip dysplasia or a shortened femur, the involved leg's tibia is typically positioned behind the uninvolved side. This phenomenon occurs because the hip joint's dysplasia can lead to a functional shortening of the limb, resulting in altered biomechanics during standing and walking. When one leg is shorter, the body naturally compensates by shifting the position of the other leg to maintain balance and proper alignment.

Specifically, the tibia on the affected side will be less advanced in its forward position during ambulation compared to the unaffected leg. This adjustment helps to stabilize the individual and allows for smoother locomotion, despite the anatomical discrepancy. Consequently, individuals with a shortened femur or hip dysplasia often display a gait pattern where the involved leg lags behind the uninvolved side during movement, which is consistent with the mechanics of walking and posture in such conditions.