The soft tissue sarcomas (STS) are a diverse collection of malignant tumours of the connective tissues arising from the primitive mesoderm and ectoderm. While the primary treatment of most is surgery, chemotherapy can be offered to patients presenting with locally advanced or metastatic disease although sarcomas are resistant to the majority of anticancer drugs. The reasons for this are not fully understood but it is thought that p53 abnormalities and mdm2 overexpression may be involved. Samples from twenty eight adult patients with soft tissue sarcomas have been analysed for p53 mutations in exons 4 to 9 both by denaturing high performance liquid chromatography (dHPLC) and by direct automated sequencing. By sequencing we found mutations in 7/28 patients, giving a mutation rate of 25%. 4/6 were point mutations in exons 5, 7 and 8 and the remaining three were deletions in exons 4, 7 and 8. Six of these samples gave abnormalities in dHPLC analysis with a concordance rate of 97.5% between the sequencing and dHPLC data. Thirty nine and forty samples have been assessed by immunohistochemistry for p53 and mdm2 expression respectively. Do7 antibody which recognises the N terminus of p53 and F4-14 which recognises the carboxy-terminus of mdm2 were used. Immunohistochemistry was scored semiquantitatively by two independent observers and the results scored accordingly: low (< 20%), intermediate (20–80%) and high (> 80%). The initial results showed that 23/40 (58%) of patients were high staining for mdm2 in contrast to only 15/39 (38%) of patients for p53. All patients with deletions in p53 had intermediate staining for mdm2. 2/3 of these had intermediate staining for p53 and 1/3 had high staining for p53. One patient with a point mutation had high staining for both p53 and mdm2 but the other two have yet to be analysed by immunohistochemistry. These results confirm the overexpression of mdm2 in STS. Future experiments are planned using fluorescent in situ hydridisation (FISH) to determine whether MDM2 amplification is one of the mechanisms involved in mdm2 overexpression.

We report the complications of prophylactic pinning of slipped upper femoral epiphysis with Crawford Adams pins in 95 cases. Complications of pin placement were seen in 13.7%. Although seven hips had penetration of the joint, there were no cases of chondrolysis or avascular necrosis. Excavation of the lateral femoral cortex was required at pin removal in 12.5% of cases. Analysis of the growth around pins allowed recommendations to be made regarding pin protrusion. The use of improved fixation devices may reduce the need for multiple pins.

The results of open reduction of the severely slipped upper femoral epiphysis are reported for 115 hips with an average follow-up of 12 years 11 months (range 2 to 33 years). In 70 hips with a chronic slip and an open growth plate the incidence of complications was low: two developed avascular necrosis, five chondrolysis, and one had both. There were more complications in the 38 hips with an acute-on-chronic slip: six developed avascular necrosis, one chondrolysis, and three had both. Of the seven hips operated upon with a partially fused plate, only one did well. All these complications were obvious within the first year but there were also three hips in the series in which osteoarthritis developed between 10 and 20 years after operation.

Fifty-three failed knee replacements were revised using minimally constrained implants with smooth uncemented intramedullary stems and metal-backed tibial components. Polymethylmethacrylate was used only to replace lost bone near the surface of the implant. Excluding four knees which had serious postoperative complications, 91% had successful relief of pain, 84% had over 90 degrees of movement and 80% could walk for more than 30 minutes. Review of the radiographs showed that there were no progressive lucencies at the interface between bone and cement, and no subsidence of components or changes in alignment. At the uncemented stem-to-bone interface, thin white lines developed near the metal, and their significance is discussed. This revision technique is an effective treatment for aseptic failure of primary total knee arthroplasty.

The essentially satisfactory results from the ICLH implant as used until 1975 were marred by examples of loosening and sinking of the tibial implant, by patellar pain of varying severity, by wear of the tibial implant caused by fragments of cement and by failure consistently to control the alignment of the leg. This report describes the methods now being used to overcome these complications and gives an account of the success so far achieved.

A multi-centre clinical trial of ICLH (Freeman-Swanson) arthroplasty has been in progress since 1971. In this paper the results up to two years after operation are reported in seventy-one knees displaying at least 30 degrees of fixed flexion, 25 degrees of valgus or 20 degrees of varus, before operation. It has been found that knees displaying 70 degrees of fixed flexion, 70 degrees of valgus, 30 degrees of varus or 50 degrees of valgus/varus instability can be satisfactorily aligned and stabilised with acceptable function. Three knees required revision. The other complications are listed and were unremarkable in nature. These results depend upon the prosthesis and upon the operative technique. The latter avoids damage to healthy bone but does involve the replacement of the tissues in the midline of the knee.