Q: Is it a problem if one of my legs is shorter than the other?
A: Only if it is causing pain or discomfort. Most of us have legs of slightly different lengths, and this causes no problem. But for some people this difference contributes to hip, back, knee or foot pain, especially if they begin an exercise program. Legs of unequal length can distort posture and thus affect the ability to withstand impact when running or walking. The pain can occur on the side of the longer or shorter leg.
The difference in leg length can be anatomical— caused by genetics or, for instance, a leg fracture. Or it may be functional—the legs are the same length but, for example, the feet hit the ground differently (most often one foot rolls slightly inward), so that one leg is effectively “shorter.” If your pelvis is asymmetrical, or you have a muscle imbalance on one side, or you’ve had a total hip replacement, it may seem that one leg is shorter.
It is nearly impossible to measure your own legs accurately. The best way is with X-rays, but this is rarely necessary. It’s usually sufficient for a health care provider to observe your gait carefully and use a tape measure to measure your legs. One problem: Some practitioners overemphasize the importance of small differences in leg length and/or mismeasure legs, which can lead to inappropriate treatments.
If you have an anatomical difference in leg length that is causing hip, knee, foot, or back pain, a simple shoe lift or custom-made orthotic device may help. If it’s a functional problem, exercises may be recommended; a physical therapist can help.