Leg length discrepancy means one leg is longer. Everyone has some side to side difference and 30% of people have a difference up to 15 mm without problems. There are many causes, however, usually a specific cause cannot be found. A leg length difference is usually not painful and small leg length differences are often unrecognized. Children generally compensate well. There are reports of association with arthritis or back problems. However, other studies contradict these findings. Gait studies show that leg length differences less than 2 cms result in little if any changes in gait. Larger differences lead to increased joint stresses which may lead to arthritis in the long run. Diagnosis is by physical examination and xrays. For a growing child, estimates
estimates are made of remaining growth. Small differences less than 2 cm require no treatment, but if desired a shoe lift can be used. Differences up to 5 cm (2 inches) should be treated with a shoe modifications or a growth slowing surgery. A large discrepancy can be addressed with a prosthesis or lengthening of the short leg using distraction osteogenesis.