Determination of femoral head containment during gait.

Using three-dimensional gait data, a mathematical model of the proximal femur was developed that will predict the loading conditions in the child's hip joint during walking. The model is based on knowledge of rim coordinates of the acetabulum, and consists of rotating unit vectors emanating from the center of the epiphysis. The results will be used in a variety of three-dimensional stress analyses of the femoral head in Legg-Perthes disease (a disorder of femoral head collapse).