Difference in leg length in children with coxa plana during and after treatment using unilateral unloading.

In unilateral coxa plana a shortening of the affected leg can often be found. This shortening affects not only the caput-collum part of the femur but also the other parts of the femur and the tibia. In this study, however, the immobilization of the affected leg seemed to be the main reason for the observed difference in the leg length. Children who had not unloaded their affected leg as carefully as they should proved to have a smaller difference in leg length than those who had unloaded their affected leg according to the instructions. On the other hand compensatory growth of the affected leg was found when both legs were again taking weight. The difference in the leg length was significantly reduced one year after the completion of the treatment.