Total avascular necrosis of the capital femoral epiphysis in congenital dislocated hips.

Ninety-four hips involved with total avascular necrosis in the treatment of congenital dislocation of the hips were reviewed in a search for etiological factors and effective salvage procedures. Pre-reduction traction and adductor tenotomy did not prevent avascular necrosis. Abduction of the hip in the "frog" position was the incriminating common denominator. This position may cause (1) interference of the blood supply to the femoral head by compression of the medial branch of the deep profundus artery; and (2) pressure on the intraepiphyseal grooves by the glenoid labrum. The containment of the femoral head by acetabuloplasty (preferably) below age 8, followed at a later date (over age 10) by transfer distally of the greater trochanter, with the abductor muscles, offers a satisfactory salvage procedure.