Limb length discrepancy is a difference between the lengths of the arms or legs. Except in extreme cases, differences in arm length do not usually impact how the arms function and do not require treatment. For this reason, this article focuses on differences in leg length.
A discrepancy in leg length will usually become obvious to parents as they watch their child grow and begin to crawl and walk. Some children are born with legs of different lengths. In other cases, illness or injury causes a discrepancy in length to develop over time. While a slight difference in leg length may not cause symptoms, a significant difference can cause a noticeable limp and make it difficult for a child to run and play.
The effects of limb length discrepancy vary from patient to patient, depending on the cause and size of the difference.
Patients who have differences of 3-1/2 to 4 percent of total leg length (about 4 cm or 1-2/3 inches in an average adult) may limp or have other difficulties when walking. Because these differences require the patient to exert more effort to walk, he or she may tire easily.
Some studies show that patients with limb length discrepancies are more likely to experience low back pain and are more susceptible to injury. Other studies do not support this finding, however.
Treatment for a discrepancy depends upon the severity. In many cases, a minor difference in leg length can be evened out by wearing a lift in one shoe. A child with a more significant difference, however, may benefit from surgery to make his or her legs the same length. This can be done in a number of ways but is most often accomplished through a procedure that slows or stops growth in the longer leg.
If you or your child seems to have a limb length discrepancy, it's important that you get it checked out. Click here to book an appointment and have it assessed.