Residual Perthes Deformity and Surgical Reduction of the Size of the Femoral Head

Legg-Calvé-Perthes disease commonly leads to substantial deformity of the femoral head and proximal femur. A nonspherical femoral head can lead to a secondary distortion of the acetabulum and premature osteoarthritis of the hip. Several surgical treatment options are available to improve the morphology of the proximal femoral epiphysis and thus the biomechanics of the hip. Advancing the greater trochanter addresses some of the extra-articular impingement. Depending on the quality of cartilage of the aspheric femoral head, the intra-articular deformity can be helped with intertrochanteric osteotomies, either valgus or varus, to bring the good cartilage into the weight-bearing area of the acetabulum. Unfortunately, these osteotomies produce secondary deformities such as a shortened femoral neck with further weakening of the abductor complex. This article describes new surgical techniques that create relative lengthening of the femoral neck and a reduction of the size and improvement in the sphericity of an excessively large and extruded femoral head. These techniques are intended to restore the congruence of the affected hip joint.