Prognostication of proximal femoral growth disturbance after Perthes' disease.

Disturbance of proximal femoral growth associated with Perthes' disease was investigated retrospectively with the use of serial radiographs of 48 patients with unilaterally affected hips. Two types of proximal femoral growth abnormalities--moderately disturbed (6 patients) and severely disturbed (13 patients)--were observed and classified based on resultant femoral length shortening and femoral head deformity of affected hips. Proximal femoral growth disturbance after Perthes' disease was dependent on age at clinical onset: patients whose age at onset was greater than 8 years had a poor prognosis. Future femoral length shortening and femoral head deformity were also found to correlate with the extent of epiphyseal and physeal involvements and the acetabular coverage of the femoral head at the stage of regeneration of involved epiphysis. The current results raised the possibility that the severity of proximal femoral growth disturbance and abnormal growth patterns could be prognosticated based on the extent of epiphyseal and physeal involvements and on the lateralization of femoral head estimated on radiographs during the early stages of Perthes' disease.