Cervical myelopathy is an uncommon but potentially fatal complication of rheumatoid atlanto-axial subluxation. Computerised myelotomography with three-dimensional reconstruction shows that rheumatoid pannus, together with the odontoid peg, contributes significantly to anterior cervico-medullary compression. These findings were the basis for treatment by transoral anterior decompression and posterior occipitocervical fusion, which removes both bony and soft-tissue causes of compression and allows early mobilisation without major external fixation. We report encouraging results from this combined approach in 14 patients who had progressive neurological deterioration.

The results of vascularised rib graft transfers are analysed in 25 patients followed up for more than two years (average 34 months). Radiographs showed early and rapid incorporation of the grafts in 4 to 16 weeks (average 8.5 weeks); external immobilisation averaged 11 weeks (range 5 to 24 weeks). The technique seems a useful alternative to allografts or homografts employing an avascular rib or fibula since it promotes rapid healing without needing microsurgical techniques.

We report seven cases of patients with seropositive rheumatoid arthritis in whom involvement of the thoracic and lumbar vertebrae occurred. Histological corroboration is presented in four. Pathological lesions comprised various combinations of paravertebral joint erosions, erosive discitis, anteroposterior and rotatory instability, major lumbar nerve root compression, and vertebral collapse. Specific radiological features are presented, enabling a distinction to be made between pure degenerative spondylosis and rheumatoid spondylitis. We submit that subcervical rheumatoid spondylitis is commoner than is generally believed, though less common than rheumatoid involvement of the cervical spine.

The lumbar spines of 22 patients were examined for disc degeneration by magnetic resonance imaging (MRI) and by discography. The results from 50 intervertebral discs visualised by both techniques were independently assessed and graded on a five-point scale from normality to gross degeneration and then compared. In 44 discs the results agreed. Of the six discs which gave differing results, four discrepancies were due to observer error and two to incorrect placement of the discographic needle. MRI was shown to be more accurate than discography in the diagnosis of disc degeneration. It has several major advantages, which should make it the investigation of choice.

We report a case of post-traumatic compartment syndrome of the biceps-brachialis compartment after a minor injury. The condition is well recognised after a drug overdose, but surgeons should be aware that a compartment syndrome may also be caused by apparently trivial trauma, and that it may develop in regions other than the anterior compartments of the leg and forearm.

We report a series of 12 Silastic interposition arthroplasties of the shoulder. There was a very high incidence of dislocation or fragmentation (50%) leading to early failure of the device in seven patients. Our analysis suggests that the operation should be restricted to rheumatoid arthritic shoulders in which there is no loss of bone or distortion of the humeral head.

Isolated traumatic dislocation of the radial head in children is not as rare as sometimes supposed. Attention to detail in radiographic interpretation is the key to diagnosis. Early closed reduction and immobilisation in an above-elbow plaster in 90 degrees of flexion and full supination for three to six weeks is recommended. Seven cases are presented, two of which were treated operatively and had unsatisfactory results. The applied anatomy, management and complications are discussed.

Exposure of the hip by osteotomy of the anterior part of the greater trochanter is described. This maintains the continuity of the tendinous junction between the anterior half of gluteus medius and the vastus lateralis and preserves intact the insertion of gluteus minimus into the anterior surface of the trochanter. The nerve supply to these muscles is not compromised and good abductor function is retained. The approach can be extracapsular or intracapsular. Reattachment of the osteotomised fragment is simple, and upward displacement after operation, as sometimes seen after complete osteotomy of the greater trochanter, cannot occur.

Twenty-six patients with femoral neck fractures were treated by open reduction, cancellous screw fixation and free fibular grafting. The patients were between 14 and 50 years of age. There were 16 old and 10 fresh fractures. Four patients had radiological signs of avascular necrosis before the treatment was instituted. Bony union was achieved in all patients except one, where the failure occurred because of a technical error. The patients were followed up for at least two years. No new case of avascular necrosis was detected after treatment, and there was clinical and radiological improvement in all four patients with pre-operative avascular necrosis.

Review of the radiographs of 882 consecutive metal-to-polyethylene hip replacements after a mean follow-up of 6.8 years showed 72 cases (8%) of aseptic femoral loosening, all of which showed a lucent zone or black line between metal and cement. In 97% of the series this appeared within two years of the arthroplasty. Progress of loosening was unpredictable and only 24% had significant symptoms. Improved technique with methylmethacrylate cement in Stanmore prostheses had reduced loosening after two years from 7.9% to 0.4%. Methods of detection of early loosening are discussed.

A patient with recurrent dislocation of the hip is described. The initial injury had been a posterior dislocation without associated fracture of the acetabular wall, and the hip had not been immobilised or protected from weight-bearing during treatment. Exploration of the hip for recurrence revealed disruption of the posterosuperior acetabular labrum with formation of a pouch between the posterior acetabular wall and the short rotator muscles. We have found no previous report of this lesion, which resembles a Bankart lesion of the shoulder. Repair using a bone block is described.

Eleven patients with tears of the acetabular labrum are discussed and the syndrome of the torn labrum is defined. In all cases the lesion was associated with acetabular dysplasia, and a constant early radiological sign was a cyst in the lateral aspect of the acetabulum. The diagnosis was confirmed by arthrography. It is suggested that these tears are degenerative, occurring as a consequence of abnormal stresses imposed by the uncovered lateral portion of the femoral head. Once a tear is present a localised stress point occurs on the femoral head, leading rapidly to degenerative arthritis.

In juvenile chronic arthritis the hips are commonly affected and this becomes the most important reason for losing independence and mobility: the joint develops a painful flexion contracture with marked loss of movement. Soft-tissue release operations consisting of psoas and adductor tenotomies have proved a safe and effective method of relieving pain and improving function. We report 89 such operations in 52 patients. More extensive soft-tissue release operations or synovectomy of the hips offer no advantage and recovery is often more painful and prolonged.

We describe a new method for the accurate measurement of the angle of anteversion of an acetabular cup from standard anteroposterior radiographs, and provide the conversion tables required. The effect of the centering of the radiograph is discussed and a method of distinguishing between anteversion and retroversion by using a caudally directed x-ray beam is described.

The clinical and pathological findings in a case of early avascular necrosis of the femoral head following renal transplantation are described. Regions of subchondral bone distant from the principal lesions showed increased numbers of empty osteocytic lacunae. This has been quantified and it is suggested that a loss of osteocytes is perhaps one of the earliest lesions leading to established avascular necrosis.

Articular cartilage from the femoral heads of 27 patients having an arthroplasty for subcapital fracture was studied, and its mechanical and chemical properties compared to those of a group of 33 age-matched macroscopically normal autopsy specimens. Water and proteoglycan contents were measured, as were swelling ability, compressive and tensile strength of the cartilage, and the density of the underlying bone. Cartilage from the fracture specimens had a significantly reduced proteoglycan content, as measured by fixed charge density, and increased swelling ability. These results indicate that this group differs from the "normal" population and care should be taken before they are accepted as control material for studies on osteoarthritic cartilage. Another finding was that bone density was much the same in the fracture and the normal group. This casts some doubt upon the concept that patients who sustain subcapital fractures are more osteoporotic than the average for the same age range.

In 42 amputations (28 below-knee and 14 above-knee), healing of the stump was found to correlate with the pre-operative transcutaneous oxygen pressure (tcPO2) measured at the planned site of incision. Of 31 patients with a tcPO2 of 30 mmHg or more, 27 healed primarily, three had delayed healing and one failed to heal; of seven patients with values between 20 and 30 mmHg three healed primarily and four had delayed healing; and all four patients with a value below 20 mmHg had stumps which failed to heal and needed reamputation. It is concluded that a tcPO2 of 20 mmHg or more at the intended site of amputation indicates that the wound will heal.

Avascular necrosis is an iatrogenic complication of the treatment of congenital dislocation of the hip. In order to assess the incidence of this and other complications, we have reviewed a consecutive series of 211 children treated at some stage with the modified Denis Browne splint used in Adelaide. In 173 children treated with this splint alone for 238 subluxed or dislocated hips which were stable when reduced, six hips (2.5%) developed radiographic avascular necrosis, though there was progressive growth deformity in only one. There was a much higher incidence among cases treated for unstable reduction by tenotomy, plaster spica and then the splint, 20 of 33 hips (60.6%) showing radiographic signs, though only one led to progressive abnormality. Of seven patients treated by adductor tenotomy and the splint no case of avascular necrosis was encountered. In the whole series the incidence of significant long-term growth disturbance in children treated in this splint was 0.7%. The great majority of our cases of avascular necrosis were attributable to manipulation and plaster, not to the subsequent use of a splint.

A new dynamic classification of Paget's disease is proposed, incorporating both the radiographic phases of bone remodelling and the scintigraphic findings. Osteolytic, mixed and osteoblastic phases are associated with increased scintigraphic activity, while the osteosclerotic phase of remodelling is associated with normal or diminished activity and an osteoblastic radiographic appearance. Abnormal modelling of bone leading to deformity is produced by accelerated apposition or absorption at the periosteal and endosteal envelopes of the bone. In 112 patients with symptoms from Paget's disease, 527 lesions were classified. The most frequent remodelling phase was the mixed one and the most common modelling state was bone expansion with endosteal and periosteal apposition. Of 88 patients treated medically, 12 had lesions which progressed to increased bone formation without a change in modelling, and the active lesions in seven patients became inactive. Prolonged treatment with disodium etidronate led to progressive osteopenia in 11 patients.

Of 66 recruits who sustained stress fractures during basic training and returned to training after a period of rest, seven (10.6%) suffered recurrent fractures within one year. None of the recurrences was at the original anatomical site. All of the recruits with recurrent stress fractures had had at least one of their initial stress fractures in the femur. This suggests that a femoral stress fracture carries a high risk of recurrence at other sites.

The term "floating knee" describes the flail joint resulting from fractures of the shaft or adjacent metaphyseal region of the ipsilateral femur and tibia; we have reviewed 15 children with this combined injury seen at the Winnipeg Children's Hospital. All had been involved in motor vehicle accidents, eight having been struck while cycling; the biomechanics of such an injury have also been studied. Treatment is difficult and the regimes varied. Results were poor when both fractures were treated nonoperatively and we recommend that at least one of the fractures should be rigidly fixed.

We have made a retrospective comparison between the results of 49 high tibial osteotomies and 42 unicompartmental replacement arthroplasties performed for the treatment of osteoarthritis of the knee, assessed 5 to 10 years after operation. The type of operation depended on the policy of the consultant responsible for treatment but analysis of the pre-operative findings showed that the two groups were sufficiently similar for direct comparison between them. In the replacement group, 32 (76%) were good, 4 were fair, 3 were poor and 3 had been revised. In the osteotomy group 21 (43%) were good, 11 were fair, 7 were poor and 10 had been revised. It was concluded that, in this series, the results of unicompartmental replacement were significantly better and that this group had shown no sign of late deterioration.

We have reviewed 40 patients after replacement of a ruptured anterior cruciate ligament with a free graft of the medial third of the patellar tendon, combining this in 17 of the cases with a MacIntosh extra-articular tenodesis. The average age of the patients at operation was 25.4 years; instability of the knee had been present for 1.5 to 9 years, and the mean follow-up was 2.9 years. The results, assessed on subjective stability, were good in 29 patients, over half being able to return to their original sport, and fair in eight. The technique of operation for free patellar tendon grafting is described in detail and the indications for this and for an additional MacIntosh tenodesis are discussed.

Untreated anterior cruciate ligament injuries in 97 knees of 87 patients were reviewed after a mean interval of six years. After their initial recovery 63% of the patients were able to return to their pre-injury sport, but six years later 27% of them had deteriorated to the extent that they could not cope with the same level of sport. Radiological deterioration was maximal in those that had had a meniscectomy more than five years before review. Knees with intact menisci were often radiologically normal despite continuing instability.

We have analysed the initial displacement and the retention of position after reduction of 192 spiral fractures of the tibial shaft. In fractures with an initial lateral displacement of one half the width of the shaft or more, successful retention of position after the primary closed reduction was achieved in only 18%. The direction of displacement between the tibial fragments showed little variation; the proximal fragment was always medial and anterior to the distal. This resulted in an increased space between the proximal tibial fragment and the shaft of the fibula in the plane of the interosseous membrane. There was a strong correlation between the initial displacement and the initial shortening. No evidence of a posterior soft-tissue hinge, able to facilitate closed reduction, could be found. Consequently, in treating severely displaced spiral fractures, open reduction and internal fixation or a few weeks' initial calcaneal traction seem to be the rational alternatives.

Sixty-nine heels in 42 patients with prominence of the calcaneus sufficient to cause symptoms were operated upon after conservative treatment had failed. At review the overall results of operation were found to be poor.

Weakness of dorsiflexion of the foot is a common complication of proximal tibial osteotomy and it has been suggested that this may be caused by an anterior tibial compartment syndrome. A prospective study of 20 patients undergoing tibial osteotomy was undertaken, in which compartment pressures were recorded and related to clinical signs. In 10 of the patients, the operation site was drained, and in 10 no drainage was employed. The undrained group showed significant elevation (greater than 45 mmHg) of the anterior compartment pressure in seven patients, and five of these had transient clinical signs. Only one patient had any permanent deficit, a minor asymptomatic weakness of extensor hallucis longus. In the drained group the pressures remained below 30 mmHg in all except two patients, who both had only a minor pressure rise and no significant early clinical signs. However, two patients from this group later developed weakness of dorsiflexion, probably due to common peroneal nerve injury, the cause of which is not clear.

Partridge bands have been developed and marketed on the assumption that their ribbed under-surface would ensure less interference with periosteal and cortical blood flow than other cerclage systems. Three cases are reported of serious clinical complications from loss of cortical bone under the band, and interference with the external bridging callus response.

Two girls with congenital postural deformity of the wrist associated with deformity of the feet are reported. Fetal position in utero is discussed as a likely cause, and treatment by simple manipulation is recommended.

For clinical, psychological and social reasons the diagnosis of Duchenne muscular dystrophy should be established as early as possible. In a survey of 83 families with 93 affected boys, the diagnosis was missed in every case referred to an orthopaedic surgeon (37 patients). In the whole group there was a mean delay of 2.0 years (0 to 6 years) during which time inappropriate treatment, difficulties in communication with parents, much parental anxiety and further pregnancies occurred. A serum creatine kinase estimation is a simple outpatient test which should be carried out on any boy with clumsy or abnormal gait, with flat feet or with an unexplained equinus deformity.

Thickening of the fibrous element of a peripheral nerve may be caused by repeated friction, traction, constriction, ischaemia or partial rupture. The sequel may be a conduction disorder and a clinical condition such as an entrapment neuropathy or a tardy nerve palsy. Neural fibrosis is typically associated with a pseudoneuroma in continuity which has resulted from scarring and adhesions around the nerve as well as proliferation of the fibrous element within the nerve; the fibrosis may be classified as extraneural, intraneural or dispersive. We report 17 cases treated by external neurolysis, with 14 satisfactory results, and 42 patients treated by internal neurolysis with success in 37. Seven of the eight failures were in cases of dispersive fibrosis. A technique of internal neurolysis is described.

Between 1980 and 1984 nine adult patients in the renal unit of Guy's Hospital developed bone and joint infection. The commonest site of infection was the spine. In this series two patients died, a mortality of 22%. The purpose of this paper is to illustrate the pitfalls in the diagnosis and management of bone and joint infection in patients with renal failure and renal transplants.