If one of your child's legs is longer than the other leg, he or she has a common problem known as leg length discrepancy. A typical difference in leg length can be anywhere from one centimeter, which usually does not cause any problems, to more than six centimeters. The greater the discrepancy, the more your child must compensate his or her normal posture and walking pattern in day to day life, which can lead to a variety of symptoms, such as functional scoliosis, hip, knee and ankle problems.
There are generally two kinds of leg length discrepancies:
- Structural discrepancy occurs when either the thigh (femur) or shin (tibia) bone in one leg is actually shorter than the corresponding bone in the other leg.
- Functional discrepancy occurs when the leg lengths are equal, but symmetry is altered somewhere above the leg, which in turn disrupts the symmetry of the legs. For example, developmental dislocation of the hip (DDH) can cause a functional discrepancy. In DDH, the top of the leg bone (femur) that is not properly positioned in the hip socket may hang lower than the femur on the other side, giving the appearance and symptoms of a leg length discrepancy.
How Boston Children's Hospital approaches leg length discrepancy
Depending on the severity of your child's condition, doctors may or may not require surgery to treat the leg length discrepancy. But if the condition is severe enough to require surgery, doctors at Children's are committed to working with you and your child to weigh all the available options, taking into consideration recovery time, possible side effects and your child's individual physical needs.