Fifty-six patients with displaced malleolar fractures had open reduction and fixation of the fracture fragments using, by random selection, either biodegradable implants or metal AO plates and screws. The cylindrical biodegradable implants were made of polylactide-glycolide copolymer (polyglactin 910). The complications, radiographic results and functional recovery were studied prospectively. After follow-up of at least one year, no significant differences emerged in the complication rate or in the results of treatment between the two methods of fixation. Because of the advantage of avoiding the need to remove metal fixation after union, we now use biodegradable internal fixation routinely to treat displaced malleolar fractures

Out of a total of 623 patients who, over a ten-year period, underwent primary total knee replacement (TKR) without patellar resurfacing, 20 underwent secondary resurfacing for chronic anterior knee pain. They were evaluated pre- and postoperatively using the clinical and radiological American Knee Society score. The mean follow-up was 36.1 months (12 to 104). The mean knee score improved from 46.7 to 62.2 points and the mean functional score from 44.7 to 52.2 points. Only 44.4% of the patients, however, reported some improvement; the remainder reported no change or deterioration. The radiographic alignment of the TKR did not influence the outcome of secondary resurfacing of the patella. Complications were noted in six of the 20 patients including fracture and instability of the patella and loss of movement. Anterior knee pain after TKR remains difficult to manage. Secondary resurfacing of the patella is not advocated in all patients since it may increase patient dissatisfaction and hasten revision

Ten patients with humeral shaft fractures and no clinical or radiographic signs of healing after at least six weeks' immobilisation were treated by flexible intramedullary nailing using a closed retrograde technique. Bone grafting was not performed, and active movement was encouraged after operation. Nine fractures healed; the mean time to union was 10.5 weeks (range 6 to 22 weeks). One patient needed compression plating and bone grafting at 22 weeks, and another required re-operation for distal migration of the rods. There were no infections, nerve palsies or other complications. Stiffness of the shoulder which had developed during early treatment improved after operation

Twenty-one patients with spinal brucellosis were reviewed. The disease is difficult to diagnose, and is often confused with spinal tuberculosis. Our study showed that it was best diagnosed by serology and bacterial culture; radiography and scanning were less helpful in the early stages. After only six weeks' antibiotic treatment, there was a 55% clinical and serological reactivation rate: better results were achieved after at least three months of treatment. The adequacy of treatment was best monitored with repeated agglutination titres, and the duration of treatment proved to be more important than the antibiotic agent itself. Surgical intervention was reserved for biopsy, severe neurological impairment, or for spinal stabilisation

Six boys with fragmentation of the proximal pole of the patella are reported; the condition was bilateral in one. Four of the six presented with symptoms of Osgood-Schlatter's disease or Larsen-Johansson disease of the same or of the contralateral knee, but they had no symptoms or signs relating to the proximal pole of the patella; one also had features suggesting minimal chondromalacia patellae. Two boys had no objective abnormality in either knee. It is suggested that the fragmentation may be a further form of traction osteochondritis of the attachments of the quadriceps mechanism. Attention is drawn to its characteristic radiographic appearance, its association with other forms of juvenile traction osteochondritis (which are commonly symptomatic), and to its occurrence in boys aged 10 or 11 years

Four infants between 2 and 13 weeks of age developed vertebral osteomyelitis. Their symptoms were different from those of children with discitis in that our patients were systemically ill, there was almost complete dissolution of involved vertebral bodies with either normal or nearly normal adjacent vertebral endplates, and three of the four children had recurrence of infection. The importance of long-term antibiotic treatment is emphasised. Years later the radiographic appearance of these children can be identical to congenital kyphosis with either anterior failure of segmentation or posterior hemivertebrae. The treatment should be the same as for congenital kyphosis with early bracing in extension and early fusion for progressive kyphosis

The intermetatarsophalangeal bursa was investigated by dissection, radiography and injection. In the web spaces between the second and third and the third and fourth digits the bursa lies superior to the transverse metatarsal ligament but projects distally to it, closely applied to the neurovascular bundle. Tissue from the web spaces of patients with classical Morton's metatarsalgia often shows lymphocytic infiltration, with additional fibrinoid necrosis of the bursal wall. It is suggested that inflammatory changes in this bursa could account for the pathological and histological findings in this condition. The bursa in the most lateral web space does not extend beyond the ligament and is not in contact with the neurovascular bundle, which may explain the rarity of symptoms in this space

1. Acute osteitis as seen in a large children's hospital is described briefly. 2. Treatment of a series of cases of acute osteitis with penicillin is discussed under the headings of investigation, penicillin administration, surgical procedure, radiographic appearance and results. The findings are tabulated. 3. Recent investigations suggest that no time limit can be set to the duration of penicillin administration. At present, routine marrow puncture appears to be the only certain method of control. We see no reason to alter the dosage set out in Table III. Administration should be continued until the marrow culture is sterile. 4. The methods adopted in subacute and chronic pyogenic bone infections are described separately

We studied the reliability of the Singh classification of trabecular bone structure in the proximal femur as a measure of osteoporosis, using kappa statistics. Radiographs of fractures of the femoral neck or trochanteric region in 80 consecutive patients were assessed by six observers. The interobserver variation was large; only three of 72 radiographs were given the same classification by all six observers and the kappa values ranged from 0.15 to 0.54. The intraobserver variation showed substantial strength of agreement; kappa values ranged from 0.63 to 0.88. In 77 patients dual-energy X-ray absorptiometry was used to measure bone mineral density. The results were compared with those of the Singh classification: we found no correlation

We implanted 203 smooth-stemmed femoral components before January 1988. The femoral component used was anatomically shaped, fluted and made of titanium. Thirty-two hips were revised due to mid-thigh pain, and the femoral implant was found to be loose in all. In the 157 patients with a two-year follow-up, the Merle d'Aubigne and pain scores for completely cementless arthroplasties were similar to those for hybrid prostheses (cemented acetabular cup and cementless femoral stem). Of the 145 cases with two-year radiographic follow-up, 59 had extensive radiolucencies and 22 were unstable. The five-year cumulative survival rate was 77%. Implantation of this stem should be restricted to patients in whom cement fixation is contra-indicated

We have shown that stress fractures can be induced in the tibial diaphysis of an animal model by the repeated application of non-traumatic impulsive loads. The right hind limbs of 31 rabbits were loaded for three to nine weeks and changes in the bone were monitored by radiography and bone scintigraphy. The presence of stress fractures was confirmed histologically in some cases. Most animals sustained a stress fracture within six weeks and there was a positive correspondence between scintigraphic change and radiological evidence. Microscopic damage was evident at the sites of positive bone scans. The progression, location, and time of onset of stress fractures in this animal model were similar to those in clinical reports, making the model a useful one for the study of the aetiology of stress fractures

Aims

To report our experience with trunnion corrosion following metal-on-polyethylene total hip arthroplasty, in particular to report the spectrum of presentation and determine the mean time to presentation.

We report a series of 50 patients under 70 years of age who had an ununited femoral neck fracture treated by a Pauwels abduction osteotomy. At an average follow-up of 7.1 years, seven patients had required prosthetic replacement and 37 others were reviewed in detail. In these patients the Harris hip score averaged 91. Twenty-two hips showed radiographic evidence of avascular femoral head necrosis, but only three of these had been replaced. For active patients with non-union of a femoral neck fracture, Pauwels osteotomy provides a high proportion of good results even in the presence of avascular necrosis of the head, providing there has been no collapse. If osteotomy fails, prosthetic replacement is still possible

We have followed up a series of total hip arthroplasties performed for secondary osteoarthritis and analysed the results in relation to the osteoblastic response to the disease. This was assessed pre-operatively from the radiographic appearance, according to Bombelli's criteria (1983). Of 63 hips in 55 patients followed up for five to 13 years, 17 were hypertrophic, 24 normotrophic and 22 atrophic in type. The atrophic-type hips showed a high incidence of acetabular loosening, leading to unsatisfactory clinical results in 32%. By contrast, the hypertrophic-type hips had a low incidence of acetabular loosening, while the normotrophic type showed intermediate results. It was concluded that the osteoblastic response to osteoarthritis is closely related to acetabular loosening and to late clinical failure

Experience in the management of fourteen children with melorheostosis has been reviewed. The principal and presenting clinical features were unilateral soft-tissue contractures associated with inequality of limb length. In contrast to the disease in adults, pain occurred infrequently and was never intense. The average interval between the discovery of the clinical features and the correct diagnosis was six years. The distinctive radiographic feature in the child was an endosteal pattern of hyperostosis marked by streakiness of the long bones and spotting of the small. This differs from the usual subperiosteal or extracortical pattern of hyperostosis seen in adults. The surgical treatment of the contractures proved difficult and recurrence of the deformity was the rule. Distal ischaemia occurred when the chronically contracted and flexed joint was rapidly extended

1. A case of solitary plasmocytoma of the thoracic part of the spine, verified by necropsy, is described. 2. A brief review is given of eighteen acceptable cases of solitary plasmocytoma of bone. 3. Of the eighteen patients, fifteen were men; the five spinal tumours were all in men. 4. Diagnosis requires: a) biopsy identification of plasmocytoma; b) exclusion of the possibility of generalised myelomatosis by complete radiography of the skeleton, repeated if necessary at intervals during the ensuing two or three years or longer. 5. A tumour of brief duration, proved to be solitary by careful necropsy, cannot be placed with certainty in the group of truly solitary plasmocytomas; it might have been a precocious first lesion of myelomatosis

1. Four cases of polyostotic fibrous dysplasia are presented. 2. All are males, all show cutaneous pigmentation, and in two there has been precocious puberty. 3. The literature has been reviewed, and present conceptions of the pathology and etiology of the disease have been discussed. 4. The dysplasia if often confused with parathyroid osteodystrophy and sometimes the parathyroid glands are needlessly explored. This confusion should not arise if it is remembered that no general skeletal decalcification, and no constant changes in the blood calcium or phosphorus, occur in polyostotic fibrous dysplasia. The radiographic appearances of healing parathyroid osteodystrophy are, however, indistinguishable. 5. No effective therapy has been discovered for this disease. Pathological fractures and deformities may require treatment

Posterolateral instability of the knee is difficult to diagnose and treat. It has been attributed to failure of ligament reconstruction and has been the cause of numerous knee operations. We present a small group of patients who complained of giving way of the knee and who had an increased range of external rotation of the tibia at 90 degrees knee flexion. The patients all had similar symptoms. We describe the standing apprehension test, which was positive in every case. Anterior subluxation of the lateral femoral condyle was detected manually in four patients and confirmed by radiography and MRI in one. The medial knee pain which is often associated with episodes of instability is probably due to stretching of the posteromedial soft tissues and perhaps the saphenous nerve

Reorientation of the acetabulum may be required in adolescents and young adults with developmental dysplasia of the hip. We have carried out a retrospective review of 51 hips after triple osteotomy with an average follow-up of ten years (8 to 15). Forty-eight hips (94%) were available for review and of these 39 (81%) were improved compared with before operation, 29 (60%) scoring good or excellent. Radiographic assessment showed improvement of the average centre-edge angle by 19°, the acetabular index by 12° and the anterior centre-edge angle by 26°. The degree of osteoarthritis progressed by one grade in ten hips (21%) over a period of ten years. The satisfactory long-term clinical and radiographic results have encouraged us to continue this treatment for symptomatic acetabular dysplasia in these patients

Polyethylene acetabular cups retrieved at revision surgery were measured by a shadowgraph technique to determine linear wear, and the values were compared with those obtained from radiographs. There was a close correlation between them, although the radiographic measurements slightly underestimated the true wear. Average linear wear rates for surface-replacement components were much greater than those for conventional prostheses with femoral heads up to 32 mm in diameter. Volumetric wear, calculated using a new formula, was found to be less than previously reported in vivo, and similar in magnitude to the results of experimental wear tests in vitro. The volumetric wear rates were greatest for the surface-replacement components and, for conventional components, were found to increase in a linear manner with component diameter