The intertrochanteric osteotomy in the treatment of congenital dysplasia of the hip.

The dysplastic acetabulum develops to normal shape only if the head of the femur is in central position in the articualr cavity correct according to biomechanics of the hip joint. Anterior rotation of the neck of the femur should be reduced operatively to neutral position as soon as possible if joint congruity cannot be achieved by conservative treatment. The indication for an intertrochanteric derotation osteotomy is made in cases demonstrating a roof inclination less than 30 degrees in children age 1 1/2 to three. After the third year of age, the mutual growth-stimulating effect of the articular bodies is not important enough to be useful in treatment of dysplasia. The femoral osteotomy has to be performed intertrochanterically. If articular congruity cannot be achieved by intertrochanteric osteotomy only, an additional innominate osteotomy of the pelvis is indicated at the same stage. The results of 435 cases demonstrated a good development of the acetabular roof if the intervention was performed early, according to correctly specified indications. In cases with insufficient growth potential of the acetabular roof, resulting in an increased inclination, an additional reconstruction of the acetabular cavity is required.