Transposition of part of the pes anserinus was used to treat 96 knees in 78 patients with recurrent, habitual or permanent dislocations of the patella. The knees with habitual (48) and permanent (27) dislocations also had extensive release of superolateral contracture. The patients were reviewed at an average follow-up of 9 years 8 months. The medial stability of the patella had been improved in all the cases. There were no recurrences in 21 knees with recurrent dislocations. There were four recurrences (5.3%) in knees with habitual and permanent dislocations due to inadequate release of the superolateral contracture and incorrect transfer of the whole of the pes anserinus. Correction of these technical errors prevented further recurrence in all four cases.

Sixty-one patients with 68 osteonecrotic femoral heads, at different stages of development, were treated surgically; their average age was 36 years. Necrosis followed a fracture in 43 hips and traumatic dislocation in three. It was idiopathic in 14, cortisone-induced in seven and associated with gout in one. The operation of multiple drilling, curettage of the necrotic bone and muscle pedicle bone grafting was performed in all. Cheilectomy of the superolateral part of the femoral head and adductor tenotomy were added in cases of advanced necrosis. Of the several types of muscle pedicle used, tensor fasciae latae anteriorly and quadratus femoris posteriorly were preferred. Full weight-bearing was not permitted for five to six months. The follow-up period varied from three to 12 years. Hip pain was regularly relieved and abduction and rotation of the joints were improved. Those with post-traumatic or idiopathic necrosis did better than those with cortisone-induced necrosis.

Fifty-six patients with ununited intracapsular fractures of the femoral neck were treated by internal fixation and muscle-pedicle bone grafting. All had some absorption of the femoral neck, and many had avascular necrosis of the femoral head. At operation the sclerosed surfaces of the fractures were freshened, the avascular femoral head was decompressed and the muscle-pedicle graft was fixed with silk thread wrapped around pins. Satisfactory union occurred in 42 patients (75%), and delayed union in seven, of whom four (7%) eventually united without further treatment and three united after osteotomy. Non-union occurred in five patients and technical failure in two.

Twenty-nine patients with avascular necrosis of the femoral head after injury have been treated by operation. Multiple drilling of the femoral head was performed, necrotic bone removed and a muscle-pedicle bone graft implanted into the head and neck of the femur. In 17 of the patients the necrosis was associated with an un-united femoral neck fracture, in 11 it occurred after the fracture had united, and one case followed reduction of a dislocated hip. The hips became painless soon after operation. The patients were young (average age 35 years), and full weight-bearing was not allowed for several months. The follow-up period ranged from 22 to 64 months. The results were excellent in 20 patients, good in five, fair in three and poor in one.

Lateral instability of the patella was found after recurrent, habitual and permanent dislocations. Contracture of soft tissues lateral to the patella only occurred with habitual and permanent dislocations, but medial laxity was present in all cases. After adequate release of the lateral contracture, the medial stability was improved by transposition of the lower three-quarters of the pes anserinus to the medial border of the patella, and the patellar ligament. This created a relatively unstretchable physiological sling which ensured dynamic stability of the patella. Six recurrent, 21 habitual and nine permanent dislocations of the patella were treated by this method. Results were excellent in 21 patients, good in 13 and fair in two. The follow-up period varied from 21 to 84 months. There have been no recurrences to date.