Lower Extremity Disorders
Lower Extremity Disorders covers a multitude of disorders children may have in their lower extremities. This can include congenital defects, leg length discrepancy, and limb dificiency. Our team of specialists at Orthopaedic Institute for Children (OIC) evaluates each case to determine the specific disorder with a comprehensive assessment and diagnosis as well as a need for non-operative outcomes or operative management.
Leg Lengthening (Leg Length Discrepancy)
The thighbone (femur) and shinbone (tibia) have growth areas, called growth plates, on both ends of the bones. If a growth plate is disturbed, one leg may grow slower than the other. Some causes of growth disturbance are infection, trauma, fractures, paralysis or occurances before birth.
Leg lengthening is a surgical procedure to lengthen bones, replace missing bone or correct bone structure deficiencies. Birth defects, bone infections, traumatic injurires, or neurological disorders can cause the discrepancy either at birth or during childhood development. During surgery, physicians may attach an external frame of up to six inches to encourage growth of the affected extremity or may surgically replace or correct bone structures.
There are generally two kinds of leg length discrepancies:
- Structural discrepancy occurs when either the femur or 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, development 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.
Treatment of Leg Length Discrepancy
Since children are still growing, the goal of treatment is to correct the discrepancy that would be present at maturity and not the present/current discrepancy.
Not all children grow at the same rate, so careful analysis of a child's personal rate of growth is crucial. To estimate the discrepancy at maturity, the OIC pediatric orthopaedic physician may need to continually take measurements of a child's growth over a period of one or two years before any surgery can be considered.
Treatment may incude a shoe lift, a small surgery to slow down the growth of the longer leg, or surgery to lengthen or shorten a leg.