Twenty patients each with a fractured femoral neck had a prosthesis with a built-in ball-and-socket joint inserted. Movements at the built-in joint were compared with total hip movement immediately after operation, one month later and three months later. It was found that the built-in joint soon lost mobility and at three months was almost completely stiff. Consequently such joints cannot be expected to prevent the acetabular erosion which is liable to follow femoral head replacement for fracture.

The best treatment for a fractured neck of femur in an old person is considered by many to be replacement hemiarthroplasty which allows the patient to walk immediately on a stable, painless hip. The late results can be marred by acetabular erosion in which the metal head of the prosthesis erodes upwards into the acetabulum to give pain and disability. Here the trial of a new bipolar prosthesis with a dynamic self-aligning outer head is described in 161 fractured necks of femur. No acetabular erosion has been seen with its use over four years.

A description is given of 20 patients with winging of the scapula. The majority had suffered spontaneous severe pain in the region of the shoulder followed about two weeks later by the deformity and associated loss of function. Only in three patients was there a clear history of trauma. Some patients may have strained the arm, but in the majority no single factor heralded the problem. Most of the patients were followed up for more than two years and it became clear that functional recovery could take up to this time to be complete. However, careful examination revealed that often a slight degree of winging remained. No specific treatment apart from gentle physiotherapy was prescribed and certainly no operative procedures. It is considered that a number of these cases were examples of neuralgic amyotrophy.

Sixty-nine patients with congenital abnormality of the femur were reviewed. Their manifestation of femoral dysplasia ranged from an intact femur approximately 60 per cent of the length of the normal leg to a subtotal absence of the femur in which only the femoral condyles remained, often with a congenital fusion of the knee joint. Two groups were defined: Group I consisted of those with congenital hypoplastic femur in which the hip and knee could be made functional and where, in some patients at least, leg equalisation was possible; Group II consisted of those with true proximal focal femoral deficiency where the hip joint was never normal and the knee joint was always useless. The patients in each group were examined and evaluated with respect to clinical signs, surgical procedures performed, and prosthetic requirements and function. A protocol of treatment for both groups is suggested.

The operative technique for combined fusion of the knee and rotationplasty of the limb in the management of congenital deficiency of the femur is presented. The technique described allows earlier definitive prosthetic fitting of a child with proximal femoral deficiency; it has reduced the number of operative procedures needed to obtain the optimal function from that deficient limb; and it has enabled these procedures to be performed at an earlier age. The technique differs from those previously described and represents a significant improvement in management of the patient with femoral deficiency.

Slipped upper femoral epiphysis remains a disease of unknown aetiology. Recent evidence has bolstered speculation that the immune system may play a role in the aetiology or pathogenesis of slipped epiphysis or of one of its complications, chondrolysis. This study reports the finding of immune complexes in the synovial fluid of all but one hip affected with slipped epiphysis in a consecutive series. In seven patients, immune complexes were detected by both the Raji cell assay and C1q-binding assay; in two, by the C1q-assay only; and in one, by the Raji cell assay only. No patients had immune complexes in the serum. Twenty-one patients with synovitis of the knee or hip caused by a variety of disorders served as the control group. Two of these patients had immune complexes in their synovial fluid. It appears that the immune complexes characterise the synovitis found with slipped upper femoral epiphysis as distinct from most other synovitides.

A retrospective study of 44 diabetic patients who, between them, had 62 Charnley low-friction arthroplasties, showed a superficial-infection rate of 9.7 per cent and a deep-infection rate of 5.6 per cent. All the operations were carried out in the Charnley clear-air enclosure and prophylactic antibiotics were not used. A statistically significant increase in the overall rate of infection was found in diabetic patients when compared with non-diabetic osteoarthritic patients (P less than 0.001) and rheumatoid patients (P less than 0.01). Hence it is suggested that in diabetic patients there may well be a place for prophylactic antibiotics in hip replacement surgery in addition to the use of the clean-air enclosure.

Intertrochanteric fractures of the femur are usually classified into stable and unstable groups, partly to predict the likelihood of displacement with early weight-bearing after internal fixation. Of 82 internally fixed intertrochanteric fractures which would normally be classified as stable, 25 subsequently underwent impaction along the axis of the nail or screw; varus displacement occurred in another six. Of these 31 fractures, 10 were two-part fractures which had been anatomically reduced, and 12 were originally undisplaced. It did not seem possible to predict the subsequent instability from the pre-operative radiographs. Of the 82 fractures, 47 had been treated with a Jewett nail-plate and 35 by a Richards compression screw-plate. Two groups of stable fractures were recognised: Group 1 was undisplaced and Group 2 displaced. Axial impaction occurred in a quarter of all Group 1 fractures however treated. In Group 2 fractures it occurred in a quarter of those treated with a nail-plate, and in over a third of those treated with a sliding screw-plate. The six fractures that underwent varus displacement had all been treated with Jewett nail-plates. Penetration into the joint occurred in 10 patients, all of them in the group treated with Jewett nail-plates; four required re-operation.

We investigated the spines of 15 patients who had significant leg-length inequality as a result of femoral shaft fractures sustained after skeletal maturity but below the age of 21 years. The patients were examined at least 10 years after fracture. The spines were studied clinically and radiographically before and after correction of leg-length inequality with a shoe-raise. Lateral spinal flexion was measured from radiographs. The lumbar scoliosis associated with the leg-length inequality was compensatory: after equalisation of leg-length the overall curve and the axial rotation were corrected completely. There was also an equal range of lateral flexion to either side after correction. Minor malalignments of the whole spine remained despite correction of the compensatory scoliosis, and within the lumbar spine correction of the scoliosis had not occurred equally at all levels. No patients complained of significant discomfort and neither structural abnormalities nor degenerative changes were seen on the radiographs.

This is a prospective study of 105 knees in 91 patients with idiopathic osteonecrosis of the femoral condyles, with an average follow-up of five years in 101 knees. Forty-eight of the 75 patients in whom the body weight was studied were obese and four of the 33 patients in whom a densitometry study was done showed decreased bone density. Prognosis is unfavourable if the lesion is larger than five square centimetres and if its width is more than 40 per cent of that of the condyle. Of the 22 patients followed up after conservative treatment 80 per cent were satisfactory. Of the 11 knees treated by arthrotomy alone 55 per cent were satisfactory. Of the 31 knees treated by osteotomy (21 with associated arthrotomy) 87 per cent were satisfactory. Arthrotomy did not significantly improve the results of osteotomies. The ideal correction was to 10 degrees of valgus. Of the 37 knees treated with replacement 95 per cent were satisfactory, and the best results were obtained with the total-condylar prosthesis.

At The Hospital for Sick Children in Toronto, 21 undescended scapulae were corrected by the Woodward procedure in 20 patients over the past 18 years. The average age at operation was six years six months. The average follow-up period after operation was 8 years 9 months. Fifteen patients were girls and five were boys. All the patients had other associated abnormalities. Only one patient had a concomitant clavicular osteotomy. The average increase in glenohumeral abduction was 37 degrees. The average scapular lowering was two centimetres. Excellent or good cosmetic results were obtained in 80 per cent of patients. Ninety-three per cent of patients expressed satisfaction with the operative results. Complications were few. The Woodward procedure is a safe and relatively straightforward surgical means to effect a good cosmetic and functional improvement in a patient with a congenital undescended scapula. We do not recommend clavicular osteotomy as a routine, but it may be added to gain more correction with less risk of neurovascular compression.

The uncommon injury of mallet thumb is described, with four case reports. In diagnosis the condition must be distinguished from dropped thumb. Operative treatment is advised which, in this small series, gave excellent results.

Injury of the neck may result when a motor vehicle is run into from behind; such injury is frequently the cause of prolonged disability and litigation. We report a series of 61 patients with these injuries. A classification, based upon the presenting symptoms and physical signs has been evolved. This classification is shown to be a reliable basis for formulating a prognosis. Factors which adversely affect prognosis include the presence of objective neurological signs, stiffness of the neck, muscle spasm, and pre-existing degenerative spondylosis.

The changing incidence of idiopathic scoliosis in 672 patients who attended the Edinburgh Scoliosis Clinic between 1968 and 1982 inclusive is reported. Of these patients, 144 had infantile, 51 juvenile and 477 adolescent idiopathic scoliosis. Thirty-seven of the infantile curves progressed and 107 resolved. The relative frequency of both progressive and resolving infantile idiopathic scoliosis (given as a percentage of the total number of patients with idiopathic scoliosis) declined from 41.75 per cent in the four years from 1968 to 1971, to four per cent in the three years from 1980 to 1982. It is suggested that infantile idiopathic scoliosis is a preventable deformity and that the position in which the infant is laid may be a causative factor.

We report two patients, each with a giant-cell tumour of the distal radius treated by curettage and bone grafting. Local recurrence of the tumour occurred in the autograft and in the adjacent soft tissues in both patients, and was successfully treated by local excision; one patient also had radiation therapy. Both remain well 20 years and five years later.

We report a rare case of Albright's syndrome associated with both a soft-tissue myxoma and hypophosphataemic osteomalacia. Renal tubular function was preserved, except for glycosuria. Serum levels of 1,25(OH)2 vitamin D3 were normal. Excision of the myxoma did not influence the biochemical abnormalities, nor did standard doses of vitamin D3 or 1 alpha-OH vitamin D3. The previously reported cases of hypophosphataemic osteomalacia associated with fibrous dysplasia and mesenchymal tumours are reviewed and the underlying mechanism discussed.

Ten patients with multiple non-ossifying fibromata are reported. All had associated extraskeletal congenital anomalies such as cafe-au-lait spots, mental retardation, hypogonadism or cryptorchidism, ocular anomalies or cardiovascular malformations. The radiographic picture and the distribution of the skeletal lesions are characteristic and constant. There are lucent areas in the shaft with a sclerotic margin; these areas narrow the medullary canal or may completely fill it. It is suggested that these features characterise a new malformation syndrome, possibly allied to neurofibromatosis. After skeletal maturation is complete, the skeletal lesions may (like non-ossifying fibromata) regress and undergo spontaneous healing.

The internal pressure of simple bone cysts was found to be slightly higher than the normal pressure of the bone marrow in the contralateral limb. The pressure within the cyst was measured during drilling with a Kirschner wire; it gradually decreased as the number of drill-holes increased. The PO2 of the cyst fluid was markedly lower than that of either venous or arterial blood measured synchronously. It is suggested that venous obstruction in the bone is the likely cause of these cysts. Seven patients with simple bone cysts were treated by the multiple drill-hole method, and the clinical outcome was excellent. Multiple drilling may prove to be the treatment of choice for simple bone cysts in the younger patient, as it presents fewer hazards than other procedures.

Immunoscintigraphy using radioisotope-labelled monoclonal antibody prepared against osteosarcoma 791T cells was used to detect a primary osteosarcoma. The eight-centimetre tumour was detected using rectilinear scintigraphy of 131I-labelled antibodies. Image enhancement was achieved by subtraction of blood-pool radioactivity labelled with technetium-99m. The ratio of tumour to non-tumour uptake of radioactivity (5:1) suggested that antibody targeting of therapeutic agents is feasible.

Patients with spina bifida cystica commonly have significant disability from a combination of valgus deformity of the ankle and subtalar joints with lateral tibial torsion and plano-abduction deformity of the foot. These deformities can be corrected by a single procedure which combines a supramalleolar tibial osteotomy with a lateral inlay triple fusion. This procedure was carried out on 20 feet in 15 patients and the results were reviewed after an average of three years (range 18 months to 7 years). In 75 per cent of feet the combination of deformities was fully corrected, ulcers and callosities were eliminated in 95 per cent, the use of calipers minimised in 95 per cent, and in all patients the problem of shoe-wrecking was reduced. Complications included recurrent valgus deformity, delayed union of the tibial osteotomy and failure of midtarsal fusion.

An extremely strong mechanical bond between cement and bone was observed in three patients with cemented hip protheses who underwent revision operations. The nature of the bone--cement attachment was studied by electron microscopy. The tissue at the interface was found to be made up of viable bone alternating with areas of soft tissue containing macrophages. The important qualitative differences between this reaction and the reaction seen around inert materials such as titanium are discussed.

Dynamic muscle-tendon substitution for acute anterior cruciate deficiency in the dog was studied using the semimembranosus muscle-tendon. Nineteen mongrel dogs each had a semimembranosus transfer in one knee; as a control, the anterior cruciate ligament and the semimembranosus were released in the opposite knee. No postoperative immobilisation was used. The anterior drawer sign was assessed before and after operation and when the dogs were killed five months later. Dogs were excluded from the study if they developed infections or contractures of the hind legs. At five months, 11 dogs were available for study. The operated knees were examined histologically and evaluated using a reproducible index of arthritis based on: the macroscopic discoloration of the articular cartilage, the cellularity of the cartilage, the microscopic appearance of the articular surface, the loss of proteoglycans, the formation of osteophytes and the degree of subchondral osteosclerosis. There was no significant difference in the anterior drawer sign or the degree of arthritic changes between knees with a semimembranous transfer and the controls. Examination showed that a muscle-tendon transfer into the tibia was equivalent to transferring the muscle into the posterior capsule--the intra-articular tendon being weak but histologically viable. The transfer did not prevent the anterior drawer sign becoming positive nor the development of osteoarthritis. A second control group, in which three dogs had an arthrotomy and semimembranosus release in both their hind legs, showed that a semimembranosus release alone did not cause osteoarthritis.