The residual shortening of the affected limbs in 55 patients treated by subtrochanteric varus derotation osteotomy was compared with that in 71 patients treated with weight-relieving calipers. When last examined, 43 of the former group and 47 of the latter had reached complete or near-complete skeletal maturity. The average follow-up was 9.1 years in the osteotomised patients and 5.25 years in the conservatively treated group. The average residual shortening (0.9 cm) was identical in both groups. In most patients the initial shortening caused by the osteotomy gradually corrected as, over a period of several years, the postosteotomy angle gradually became less varus. Any residual shortening depended principally on the severity of inhibition of endochondral ossification at the proximal femoral growth plate. Less residual shortening was seen in children who were under seven years of age at the onset of symptoms (under eight at operation) in whom the open-wedge technique of osteotomy was employed and who had good anatomical results

Aims

Cigarette smoking has a negative impact on the skeletal system, causes a decrease in bone mass in both young and old patients, and is considered a risk factor for the development of osteoporosis. In addition, it disturbs the bone healing process and prolongs the healing time after fractures. The mechanisms by which cigarette smoking impairs fracture healing are not fully understood. There are few studies reporting the effects of cigarette smoking on new blood vessel formation during the early stage of fracture healing. We tested the hypothesis that cigarette smoke inhalation may suppress angiogenesis and delay fracture healing.

Ten patients who suffered iatrogenic injury to a vertebral artery during anterior cervical decompression were reviewed to assess the mechanisms of injury, their operative management, and the subsequent outcome. All had been undergoing a partial vertebral body resection for spondylitic radiculopathy or myelopathy (4), tumour (2), ossification of the posterior longitudinal ligament (1), nonunion of a fracture (2), or osteomyelitis (1). The use of an air drill had been responsible for most injuries. The final control of haemorrhage had been by tamponade (3), direct exposure and electrocoagulation (1), transosseous suture (2), open suture (1), or open placement of a haemostatic clip (3). Five patients had postoperative neurological deficits, but most of them resolved. We found direct arterial exposure and control to be safe, quick and reliable. Careful use of the air drill, particularly in pathologically weakened bone, as in infection or tumour, is essential. Arterial injury is best avoided by a thorough knowledge of the anatomical relationships of the artery, the spinal canal, and the vertebral body

The features are described of seven cases of "juxtacortical" chondrosarcoma, the term introduced by Jaffe for a rare but distinct entity and now accepted in the World Health Organisation classification as preferable to the term "periosteal" chondrosarcoma. In all cases the lesion involved the shaft of a long bone, most often the femur, and in two cases two different long bones were affected. Six of the seven patients were male and all were in the second decade. The characteristic appearance was that of a small tumour adjacent to the cortex with areas of spotty calcification often accompanied by radiating bone spicules perpendicular to the bone shaft and a typical Codman's triangle. Histologically all the tumours showed a cartilaginous lobular pattern, well limited on the surface and seldom infiltrating the cortex; areas of spotty calcification and enchondral ossification were often present but tumour osteoid and bone were conspicuously absent. Despite the ominous histological aspect, the prognosis proved to be relatively favourable compared with the usual central chondrosarcoma of a similar grade of malignancy

1. A general picture of the histological state of the bone-cement junction, up to seven years after implantation, is presented as a result of the study of twenty-three human specimens. 2. The transmission of load from cement to bone occurs at isolated points through the medium of newly formed fibrocartilage. 3. It is clear that this fibrocartilage has been produced in response to mechanical pressure on fibrous tissue which has undergone compression between cement and underlying bone. 4. Direct contact exists between the surface of the cement and the newly formed fibrocartilage at these sites of load transmission. 5. Load-bearing fibrocartilage frequently shows areas of ossification extending into it from the underlying bone. 6. Where soft tissues in contact with cement are too thick or too delicate for load transmission a thin layer of giant-cell cytoplasm coats the cement surface. 7. No collections of giant cells to form granulomatous or caseating areas have been seen. 8. Fat storage, indicating the absence of chemical irritation, can occur within ten microns of the cement surface

Clinical experience of the ICLH method of resurfacing the hip now spans 10 years. The first 36 arthroplasties, performed between 1972 and 1974, have been previously reported. This review covers in detail 204 such arthroplasties performed between 1975 and 1979 using a standard operative technique and prosthesis; these hips were consecutive and entirely unselected. Follow-up averaged 3.2 years (range two to six years). Successful hips are comparable to hips successfully replaced with stemmed prostheses. The rates of perioperative complications and failure due to infection, ectopic ossification, fracture of the femoral neck, and dislocation are favourably comparable to rates reported for stemmed total hip arthroplasties. The rate of aseptic loosening (17 per cent) greatly exceeded that found for stemmed total hip arthroplasties. Errors of patient selection, operative technique and prosthetic design have been identified. It is concluded that, although resurfacing arthroplasty of the hip may be an appealing procedure with theoretical advantages in certain instances, patient selection is essential, operative technique is demanding and changes in the design of the prosthesis are required. The procedure is still in evolution and therefore it should not yet be generally employed

A series of ten infants is reported, seven of whom showed evidence of osteomyelitis of the upper end of the femur; the remaining three did not, but presented with an acute subluxation of the hip in a febrile illness. Four sequelae among the seven more severe cases were: 1) destruction of the capital epiphysis with dislocation at the hip; 2) destruction of the capital epiphysis, the femoral neck remaining in the acetabulum; 3) destruction of the epiphysial plate with the femoral head, remaining in the acetabulum, connected to the femoral neck by a fibrous union; 4) recovery with coxa magna but no other deformity. The streptococcus plays a greater part in this osteomyelitis of infancy than in osteomyelitis of older children, but various other organisms were identified. The organism should be sought by blood culture as well as from the local lesion. Aspiration of the hip, treatment of the hip in abduction and the use of the appropriate antibiotic are recommended. If there is marked swelling and induration, freer release of the pus is strongly advised. Controlled abduction osteotomy plays a useful part in stabilising the femoral neck in the acetabulum or in stabilising the femoral neck beneath the capital epiphysis, but may usefully be preceded by an arthrograph because late ossification of a detached head sometimes occurs

Aims

CERAMENT|G is an absorbable gentamicin-loaded biocomposite used as an on-site vehicle of antimicrobials for the treatment of chronic osteomyelitis. The purpose of the present study was to investigate the sole effect of CERAMENT|G, i.e. without additional systemic antimicrobial therapy, in relation to a limited or extensive debridement of osteomyelitis lesions in a porcine model.

We describe the results of 76 total arthroplasties of the hip for stage-III or stage-IV avascular necrosis of the femoral head. Harris Galante Porous cups were used in 63 patients between 1986 and 1994 and followed prospectively. We reviewed 70 hips with a follow-up of more than five years (mean 7.6). At the latest review the mean Harris Hip Score had improved from a preoperative value of 29 ± 14.7 to 94 ± 6.8. Radiologically, there was no evidence of acetabular migration. The rate of revision for the femoral component was 8.6%, three being undertaken for loosening and three to allow downsizing of the femoral head. The rate of revision for the acetabular component was 7.1% (five cups). At the time of revision none of the cups was clinically loose, and only required the liner to be changed. The rate of complications was low with no case of deep infection or dislocation, but nine of the 76 hips (11.8%) showed grade-III heterotopic ossification. Previous studies of patients undergoing cemented total hip arthroplasty for the treatment of advanced avascular necrosis have indicated a high incidence of loosening of the acetabular component. Our findings show good medium-term results using the Harris Galante Porous cup for acetabular reconstruction, together with a variety of cemented femoral components, for the treatment of this difficult problem

From 1974 to 1989, we treated 50 patients with a simple dislocation of the hip: 38 were posterior dislocations and 12 were anterior. All dislocations primarily treated at our hospital were reduced by closed methods within three hours (mean 85 minutes (10 to 180)) and 43 were reviewed after an average follow-up of 8 years (2 to 17). It is widely held that isolated hip dislocation reduced within six hours gives an excellent outcome, but we found a significant number of complications. There were radiological signs of partial avascular necrosis in two, mild osteoarthritis in seven, and moderate degeneration in two. Heterotopic ossification was seen in four patients, but 29 of 33 MRI examinations were normal. Objective evaluation according to the Thompson and Epstein (1951) criteria showed fair and poor results in 3 of 12 anterior dislocations, but in 16 of 30 posterior dislocations. In six of the seven patients with no other severe injury, the hip had an excellent or good result; in only three of the eight patients with severe multiple injuries was this the case. The important factors in the long-term prognosis appear to be the direction of the dislocation and the overall severity of injuries

Aims

The purpose of this study is to examine six types of bearing surfaces implanted at a single institution over three decades to determine whether the reasons for revision vary among the groups and how long it takes to identify differences in survival.

The histology and mechanics of leg lengthening by callus distraction were studied in 27 growing rabbits. Tibial diaphyses were subjected to subperiosteal osteotomy, held in a neutral position for 10 days and then slowly distracted at 0.25 mm/12 hours, using a dynamic external fixator. Radiographs showed that the gap became filled with callus having three distinct zones. Elongation appeared to occur in a central radiolucent zone; this was bounded by two sclerotic zones. Histologically, the radiolucent zone consisted of longitudinally arranged cartilage and fibrous tissue while the sclerotic zones were formed by fine cancellous bone. New bone occasionally contained islands of cartilage, suggesting it had been formed by endochondral ossification. After completion of distraction, the two sclerotic zones fused, shrank and were eventually absorbed, leaving tubular bone with a new cortex. When the periosteum had been removed at the operation, callus formation was markedly disturbed and there was failure of bone lengthening. Scraping of endosteum, in contrast, did not have a pronounced effect. These results suggest that the preservation of periosteum is essential if bone lengthening by callus distraction is to succeed, and that preservation of the periosteum is more important than careful corticotomy

1. Perthes' disease is an ischaemic lesion of the ossific nucleus of the head of the femur which may vary both in extent and degree. It is probably never quite complete. 2. When part of the ossific nucleus only is affected, as is usually the case, it is almost invariably the antero-lateral part. 3. The process of absorption of the damaged bone is complete radiologically before there is radiological evidence of reossification. 4. Reossification always occurs in Perthes' disease. 5. The aim of treatment must be to see that the mould in which the head is shaped is the right shape when ossification occurs. 6. The deformity of the head of the femur does not occur from pressure alone, but from pressure combined with subluxation. Full unrestricted weight-bearing can be allowed with safety on a femoral head in which there are ischaemic changes provided the femoral head is well contained. 7. The time of treatment can be very greatly reduced by using operation to correct the subluxation instead of relying on external splintage. This can be achieved by subtrochanteric osteotomy with rotation, or rotation combined with varus angulation. 8. Perthes' disease and avascular necrosis of the head of the femur are different conditions with different characteristics. 9. Suggestions are made as to the nature of the disease in relation to absorption, continued growth and reossification

1. The technique of compression-arthrodesis of the knee joint is described. 2. Fifteen consecutive cases are reported in which clinical union was detected at the first inspection from twelve days to six weeks after operation. By this method the total period of disability is reduced to three months. 3. Three mechanical factors which might be responsible for this very early clinical union are examined: compression is believed to be the main factor, although fixation is also important. 4. A fallacy is exposed in the use of bone grafts for arthrodesis of the knee; the graft is less osteogenic than the substance of the bones which form the joint, and it provides inefficient internal fixation. 5. A theory is suggested that compression, even in the presence of slight movement, acts by producing a fixed "hinge" without shearing movement; at this point a bridgehead of flexible osteoid tissue is established in which ossification inevitably takes place despite slight bending movement. 6. A second theory is suggested that high compression forces stimulate early union by liberating bone salts at points of maximum pressure through the action of osteoclasts, and that the local excess of bone salts is redeposited under cellular activity within a range of a few millimetres where there is no pressure

Aims

Options for the treatment of intra-articular ligament injuries are limited, and insufficient ligament reconstruction can cause painful joint instability, loss of function, and progressive development of degenerative arthritis. This study aimed to assess the capability of a biologically enhanced matrix material for ligament reconstruction to withstand tensile forces within the joint and enhance ligament regeneration needed to regain joint function.

We have examined the process of fusion of the intertransverse processes and bone graft in the rabbit by in situ hybridisation and evaluated the spatial and temporal expression of genes encoding pro-α1 (I) collagen (COL1A1), pro-α1 (II) collagen (COL2A1) and pro-α1 (X) collagen (COL10A1). Beginning at two weeks after operation, osteogenesis and chondrogenesis occurred around the transverse process and the grafted bone at the central portion of the area of the fusion mass. Osteoblasts and osteocytes at the newly-formed woven bone expressed COL1A1. At the cartilage, most chondrocytes expressed COL2A1 and some hypertrophic chondrocytes COL10A1. In some regions, co-expression of COL1A1 and COL2A1 was observed. At four weeks, such expressions for COL1A1, COL2A1 and COL10A1 became prominent at the area of the fusion mass. From four to six weeks, bone remodelling progressed from the area of the transverse processes towards the central zone. Osteoblasts lining the trabeculae expressed a strong signal for COL1A1. At the central portion of the area of the fusion mass, endochondral ossification progressed and chondrocytes expressed COL2A1 and COL10A1. Our findings show that the fusion process begins with the synthesis of collagens around the transverse processes and around the grafted bone independently. Various spatial and temporal osteogenic and chondrogenic responses, including intramembranous, endochondral and transchondroid bone formation, progress after bone grafting at the intertransverse processes. Bone formation through cartilage may play an important role in posterolateral spinal fusion

We studied the cellular response to physeal distraction in the growth plates of skeletally immature rabbits. We used a new method of labelling and detection of proliferating cells with bromodeoxyuridine (BUdR) and an anti-BUdR antibody. The application of an external fixator but no distraction force produced no changes in the growth plates. After five days of distraction at a maximum force of 20 N, the growth plate became thicker, mainly because of an increase in the number of hypertrophic chondrocytes, but there was no evidence of increased cell proliferation. Recent fractures were seen at the junction of growth plate and metaphysis but the increase in bone length was insignificant. After ten days of distraction at the same maximum force, the chondrocyte columns had become disorganised and cell proliferation was significantly decreased. There was an increase in bone length due to distraction of the fracture gap. In this model, physeal distraction did not stimulate cell proliferation, but actually inhibited it. The apparent increase in growth-plate thickness produced by distraction is not due to increased cell production, but results from inhibition of endochondral ossification and the consequent accumulation of hypertrophic chondrocytes. Any growth after distraction depends on the ability of growth-plate chondrocytes to divide. The decrease in proliferative activity which we found after ten days of distraction suggests the need for caution in the use of such procedures in young children

Colchicine is often used in the treatment of diseases such as familial Mediterranean fever (FMF) and gout. We have previously reported that patients with FMF who had colchicine on a daily basis and who had a total hip arthroplasty showed no heterotopic ossification after surgery. The mechanism by which colchicine causes this clinical phenomenon has never been elucidated. We therefore evaluated the effect of various concentrations of colchicine on cell proliferation and mineralisation in tissue culture, using rat and human cells with and without osteogenic potential. Cell proliferation was assessed by direct cell counts and uptake of (. 3. H)thymidine, and mineralisation by measuring the amount of staining by Alizarin Red. Our findings indicate that concentrations of colchicine of up to 3 ng/ml did not affect cell proliferation but inhibition was observed at 10 to 30 ng/ml. Mineralisation decreased to almost 50%, which was the maximum inhibition observed, at concentrations of colchicine of 2.5 ng/ml. These results indicate that colchicine at low concentrations, of up to 3 ng/ml, has the capacity to inhibit selectively bone-like cell mineralisation in culture, without affecting cell proliferation. Further clinical and laboratory studies are necessary to evaluate the effects of colchicine on biological processes involving the proliferation of osteoblasts and tissue mineralisation in vivo, such as the healing of fractures, the formation of heterotopic bone and neoplastic bone growth

Aims

The aim of this study was to analyze the results of two radiocapitellar prostheses in a large case series followed prospectively, with medium-term follow-up.

Aims

Arthrofibrosis is a relatively common complication after joint injuries and surgery, particularly in the knee. The present study used a previously described and validated rabbit model to assess the biomechanical, histopathological, and molecular effects of the mast cell stabilizer ketotifen on surgically induced knee joint contractures in female rabbits.