Aims

Fretting and corrosion at the modular head/neck junction, known as trunnionosis, in total hip arthroplasty (THA) is a cause of adverse reaction to metal debris (ARMD). We describe the outcome of revision of metal-on-polyethylene (MoP) THA for ARMD due to trunnionosis with emphasis on the risk of major complications.

In a retrospective study of all 137 patients with soft-tissue sarcoma treated by surgery between 1972 and 1984, the clinical course was related to several host and tumour features, including the Surgical Staging System of Enneking, Spanier and Goodman (1980). Only patients free from metastasis with untreated primary lesions on admission were included. According to the Surgical Staging System, nine tumours were IA, 18 IB, 38 IIA and 72 IIB. Only 12 patients underwent amputation; 125 were treated by local surgery. The mean follow-up time was ten years (minimum five). For the whole series the probability of seven-year survival was 0.65; 42 patients (31%) died from tumour disease. All these had metastases and 24 also had local recurrence. The local recurrence rate was 36%. Multivariate analysis identified large tumour size and high histological grade as significant risk factors for metastatic disease and tumour-related death. Sex, age, tumour site, surgical margin and local recurrence showed no correlation with survival. The prognostic contribution of compartmentality was virtually nil. Histological grade combined with tumour size was found to give better prognostic information than that obtained by the Surgical Staging System

The long-term effect of stainless steel and titanium alloy plates on structural remodelling and bone mass of osteotomised canine femora was studied and the effects of early and late removal of plates were compared in 27 adult Beagles. Radiological, histological, histomorphometric and tetracycline fluorescence studies led to three conclusions. First, the continuous (60 weeks) presence of plates, irrespective of their composition, delays remodelling and leads to a reduction of bone mass. This loss is significantly greater under stainless steel plates. Secondly, the removal of plates at eight weeks leads during the 52 ensuing weeks to a marked and widespread structural remodelling and to a return to normal bone mass, irrespective of the type of plate used. However, remodelling is more intense after titanium alloy plates have been used; it is not complete 60 weeks after osteotomy. Thirdly, removal of plates at 40 weeks activates remodelling during the ensuing 20 weeks to a lesser degree and to a more limited extent than early plate removal. The clinical significance of this study is that less rigid but stable internal fixation permits the radiological assessment of healing and thus the determination of the optimal moment for removal of the plates. It also reduces the degree of bone loss should the plate be left in situ for any reason

Of tumours arising in otherwise normal bones, fibrosarcoma is about one-third as common as osteosarcoma and may have a very slightly better prognosis. A comparison of the aetiology and behaviour of forty-nine fibrosarcomata and 152 osteosarcomata indicates several similar features. Fibrosarcoma lacks the characteristic peak incidence in adolescence of osteosarcoma, but the age and sex distributions of both tumour types in patients of middle life--twenty-five to sixty-five years--are remarkably similar, even in their frequency. With fibrosarcoma, perhaps, lung metastases are fewer and appear later, thus contributing to the slightly better survival, but there is some increase in the proportion of extra-pulmonary secondaries. As with osteosarcoma, patients with fibrosarcoma show some increase in the length of post-metastatic survival when metastases are of later appearance. For the whole series the five-year crude survival rate was 21 per cent, better results being recorded for patients with histologically well differentiated tumours (30 per cent) and for long bone tumours when the patient was metastasis-free initially and the tumour was treated by prompt ablation (40 per cent). These are probably the best results one may expect for osseous fibrosarcoma without recourse to adjuvant antimetastatic therapy. Complete control of the primary tumour is likewise mandatory, and can be assured only by complete surgical removal when this is technically feasible

1. A clinical, radiological and histological description of a patient with fibrogenesis imperfecta ossium is given. We think that this is the first case in which diagnosis has been made during the life of the patient. 2. The disease is characterised by a defect in the formation of the collagen fibres of the bone matrix. There is also a failure of normal calcification of the matrix, giving rise to the appearance of wide "osteoid" seams. When examined with the polarising microscope and when stained with Gomori's reticulin stain the collagen fibres can be seen to be grossly deficient and abnormal. 3. The patient presented at the age of fifty-four years with bone pain and multiple fractures. The only biochemical abnormality detected in the plasma was an elevated alkaline phosphatase. He was also in negative calcium balance. 4. Treatment with vitamin D. 2. , later changed to dihydrotachysterol, appears to have produced clinical, biochemical and radiological improvement. It appears that a direct action of the vitamin on the abnormal bone collagen must be postulated, in addition to its known actions on the calcifying mechanisms. 5. An unusual feature of the case was the slow development of a total unresponsiveness to large doses of vitamin D. 2. , in spite of a markedly elevated level of vitamin D in the plasma. There was later a response to a much smaller dose of dihydrotachysterol, which is being maintained to date

1. One hundred cases of torticollis and 117 cases of sternomastoid tumour have been reviewed. 2. Congenital torticollis can be sub-divided into two groups: postural and muscular. 3. Congenital postural torticollis is present at birth; it is not associated with a sternomastoid tumour; it is transient in nature; and it does not require operation for its relief. 4. Congenital muscular torticollis is preceded by a sternomastoid tumour which is clinically evident in one-fifth of all cases. 5. The ischaemic theory of the causation of sternomastoid tumours is not supported by recent histological investigations. Some other cause, which probably is operative before birth, must be sought. 6. Four-fifths of all cases of sternomastoid tumours resolve spontaneously and leave no deformity. Excision of the tumour in infancy is therefore unjustifiable. 7. Open division of the muscle and of the cervical fascia in congenital muscular torticollis cures the deformity but leaves an unsightly scar. 8. Subcutaneous tenotomy can be relied upon to cure the deformity if post-operative treatment is carried out skilfully and assiduously over a prolonged period. 9. If complete correction is not gained at the time of subcutaneous tenotomy a better result can be assured by open division of the upper end of the muscle through an incision within the hair line

We investigated the effects of low-intensity pulsed ultrasound on distraction osteogenesis in a rabbit model. Callotasis of the right tibia was performed in 70 male Japanese white rabbits using mini-external fixators. In the first part of the study in 64 animals using normal distraction (waiting period seven days; distraction rate 0.5 mm/12 hours; distraction period ten days), we evaluated the distraction site by radiography, measurement of the bone mineral density (BMD), mechanical testing, and histology. In the second part in six rabbits using fast distraction (waiting period 0 days; distraction rate 1.5 mm/12 hours; distraction period seven days) the site was evaluated radiologically. Half of the animals (35) had received ultrasound to their right leg (30mW/cm. 2. ) for 20 minutes daily after ceasing distraction (ultrasound group), while rigid fixation only was maintained in the other half (control group). With normal distraction, the hard callus area, as shown by radiography, the BMD, and the findings on mechanical testing, were significantly greater in those receiving ultrasound than in the control group. Histological analysis showed no tissue damage attributable to exposure to ultrasound. With fast distraction, immature bone regeneration was observed radiologically in the control group, while bone maturation was achieved in the ultrasound group. We conclude that ultrasound can accelerate bone maturation in distraction osteogenesis in rabbits, even in states of poor callotasis

The properties of impacted morsellised bone graft (MBG) in revision total knee arthroplasty (TKA) were studied in 12 horses. The left hind metatarsophalangeal joint was replaced by a human TKA. The horses were then randomly divided into graft and control groups. In the graft group, a unicondylar, lateral uncontained defect was created in the third metatarsal bone and reconstructed using autologous MBG before cementing the TKA. In the control group, a cemented TKA was implanted without the bone resection and grafting procedure. After four to eight months, the animals were killed and a biomechanical loading test was performed with a cyclic load equivalent to the horse’s body-weight to study mechanical stability. After removal of the prosthesis, the distal third metatarsal bone was studied radiologically, histologically and by quantitative and micro CT. Biomechanical testing showed that the differences in deformation between the graft and the control condyles were not significant for either elastic or time-dependent deformations. The differences in bone mineral density (BMD) between the graft and the control condyles were not significant. The BMD of the MBG was significantly lower than that in the other regions in the same limb. Micro CT showed a significant difference in the degree of anisotropy between the graft and host bone, even although the structure of the area of the MBG had trabecular orientation in the direction of the axial load. Histological analysis revealed that all the grafts were revascularised and completely incorporated into a new trabecular structure with few or no remnants of graft. Our study provides a basis for the clinical application of this technique with MBG in revision TKA

Two acetabula which contained large bone allografts introduced at revision arthroplasty were obtained at post-mortem. The allografts had been placed in superior defects to support cementless acetabular components, and both hips were functioning well at the time of death. Clinical radiographs demonstrated apparent healing of graft to host bone, no graft collapse and stability of the acetabular components. Microscopic examination of sections through these specimens showed that the bulk allografts were encapsulated in fibrous tissue. Vascularity was increased at the host-graft interface, but there was limited evidence of bone union between the graft and the host. In the few areas where union had occurred, revascularisation extended no more than 2 mm beyond the graft-host interface. Within the body of the graft, the acellular matrix of trabecular bone maintained structural integrity up to 48 months after surgery. In areas where the allograft was adjacent to an implant, there was fibrous tissue orientated parallel to the implant surface. The acetabulum which contained a porous-coated component showed evidence of bone growth into the porous surface where it was in contact with viable host bone. No ingrowth occurred in areas where the porous coating was in contact with the graft. Although the grafts were functioning well, allograft revascularisation and remodelling were minimal, and the radiological appearance of healing did not correlate with histological findings

We have developed a bioactive bone cement (BA cement) consisting of Bis-GMA resin and bioactive glass powder. It has high compressive and tensile strengths, a low curing temperature and its bioactivity allows it to bond directly with bone. We operated on the 18 femora of nine mongrel dogs for intercalary replacement of part of the bone by a metal prosthesis using either PMMA cement or BA cement for fixation. Three dogs were killed at each of 4, 12 and 26 weeks after surgery for the evaluation of fixation strength by a push-out test and for histological examination by Giemsa surface staining and SEM. Fixation strengths with PMMA cement at 4, 12 and 26 weeks after surgery were 46.8 ± 18.9, 50.0 ± 24.7, and 58.2 ± 28.9 kgf (mean ±SD), respectively. Those with BA cement were 56.8 ± 26.1, 67.2 ± 19.2, and 72.8 ± 22.2 kgf, respectively. Fibrous tissue intervened between bone and PMMA cement but BA cement had bonded directly to bone at 12 and 26 weeks. This suggests that BA cement will be useful in providing long-lasting fixation of implants to bone under weight-bearing conditions

Aims

The aim of this paper was to investigate the prognostic factors for local recurrence in patients with pathological fracture through giant cell tumours of bone (GCTB).

Apart from preliminary notices of present work, previous reports of experimental and clinical trials of the effects of a high-peak pulsed electromagnetic field (PEMF) on degeneration and regeneration of peripheral nerves lacked statistical analysis. Therefore, we designed experiments with standardised operative, histological, cytological and morphometric techniques to assess the effect of PEMF on lesions of the common peroneal nerves in paired male rats matched for age, environmental conditions and level and type of lesion. One of two types of lesion was induced in the left common peroneal nerve: in 12 pairs of rats the nerve was crushed just above the knee and in the remaining 12 pairs the nerve was cut and immediately sutured at the same level. The right common peroneal nerve of each rat served as a control. Animals received 15 minutes of PEMF produced by a Diapulse machine or sham treatment daily for periods ranging from three and a half days to eight weeks after injury. Healthy nerves were unaffected, but after damage there were statistically significant differences between PEMF treated and sham treated rats. PEMF accelerated the recovery of injured limbs and the degeneration, regeneration and maturation of myelinated axons; epineural, perineural and intraneural fibrosis was reduced; and the luminal cross-sectional area of intraneural vessels increased after both types of lesion. Findings are discussed and the need for clinical trials is stressed

1. A study of late segmental collapse in twelve femoral heads shows that it may not develop until two and a half years after the fracture. 2. Until the articular surfaces had collapsed the patients usually had no symptoms. The fractures were united and there was no obvious radiographic evidence of ischaemic necrosis. 3. There was histological evidence that the whole of the femoral heads had been necrotic at one time. The term late segmental collapse is more appropriate than late segmental necrosis. 4. The blood vessels of the ligamentum teres played little or no part in revascularisation which, when it occurred, was almost entirely across the fracture line. 5. In only one femoral head was revascularisation approaching completion and apparently continuing. In the other eleven much of the head remained necrotic and the process appeared to have halted. 6. An increase in radiological density was caused by new bone laid down on unresorbed necrotic trabeculae and was most prominent behind the line of revascularisation when the process had halted. 7. Trabecular collapse was evident within dead bone. In ten of the femoral heads it occurred in the subchondral region and in four just beyond the junction of reossified and dead bone. 8. Osteoarthritic changes occurred in the cartilage covering revascularised bone at the periphery of the head, especially when collapse was severe

1. The methods by which epiphyses receive their blood supply was studied by means of India ink injections in monkeys. Two types were identified depending upon whether the epiphysis was entirely or partly covered by articular cartilage. In the former, nutrient vessels enter the epiphysis by traversing the perichondrium at the periphery of the plate. In the latter they enter the epiphysis by penetrating the cortex at the side of the epiphysis at a point remote from the epiphysial plate. 2. The histological changes after separation of the second type of epiphysis were also studied. After temporary interference with endochondral ossification marked by increased thickness of the epiphysial plate, healing occurred so rapidly that within three weeks it was difficult to determine that the epiphysis had been separated at all. 3. It is concluded that when nutrient vessels enter an epiphysis at a point remote from the epiphysial plate, that epiphysis can be separated without serious disturbance to its blood supply and accordingly without interference with its capacity for growth. As it has been established that an epiphysis which is entirely covered by articular cartilage cannot be separated without destruction of its blood supply and subsequent avascular necrosis (Harris and Hobson 1956), it is concluded that the prognosis of an epiphysial separation is dependent upon the degree of damage to its blood supply rather than the mechanical disturbance of the epiphysial plate

1. Histochemical studies have been made of the distribution of alkaline phosphatase, glycogen and acid mucopolysaccharides in normal growing bones (mice, rats and men) and also in forty cases of pathological bone processes (neoplastic and dystrophic). 2. The study of normal material confirmed that alkaline phosphatase is plentiful in calcification of cartilage and even more plentiful in bone formation (whether enchondral or direct). 3. It was observed that glycogen increased in the cartilage areas about to be calcified, and that it disappeared in those calcified. It seemed that osteoblasts did not always contain glycogen. 4. In the pathological material (tumours and dystrophic processes) there was great phosphatase activity in the osteogenic areas and also in the cartilage about to be calcified. Whereas glycogen was plentiful in some cases of neoplastic or reactive osteogenesis, it was absent from others. 5. In every area of normal or pathological ossification, the presence of phosphatase seems to be a rule; glycogen is often but not always present. 6. It appears that alkaline phosphatase plays an important role in the formation of the protein matrix of bone, but is not associated with the elaboration of the mucoprotein cartilage matrix. We believe it is premature to draw any definite conclusion on the behaviour and role of the metachromatic substances in the processes of calcification and ossification. The histochemical study of alkaline phosphatase has shown that this is a valuable method in the detection of reactionary or pathological osteogenic processes which in some cases are difficult to demonstrate with the usual histological methods

Aims

The aim of this review was to evaluate the available literature and to calculate the pooled sensitivity and specificity for the different alpha-defensin test systems that may be used to diagnose prosthetic joint infection (PJI).

Of the 4172 patients in a survey of all cases of tuberculosis notified in a six-month period in England and Wales in 1978-79, 198 had a bone or joint lesion; 79 were white and 108 were of Indian subcontinent (Indian, Pakistani or Bangladeshi) ethnic origin. The estimated annual notification rates for orthopaedic tuberculosis were 29 per 100 000 for the Indian subcontinent group and 0.34 per 100 000 in the white group, a ratio of 85 to 1. Rates increased with age in both groups. The spine was the most common site, and was affected in 30% of the white patients and 43% of the Indian subcontinent patients; the distribution of other sites was similar in both groups. Positive culture from a bone or joint lesion was obtained in 99 (50%) of the 198 patients (58% of white patients and 47% of the Indian subcontinent patients). Bacteriological or histological confirmation of tuberculosis either from a bone or joint lesion or from another site was obtained in 68% of the patients. Mycobacterium tuberculosis was isolated from the orthopaedic lesions in 79 of the 82 patients with identification test results and M. bovis in the 3 remaining patients. Of the 61 patients with M. tuberculosis and with no history of previous chemotherapy, 5 had resistant strains compared with 1 of the 18 patients who had previously received chemotherapy. All 6 patients with resistant strains were of Indian subcontinent ethnic origin

1. Four cases of osteomalacia secondary to vitamin D deficiency have been investigated histologically and with the electron microscope. 2. Three main types of cells were found along the osteoid tissue. Cells of Group 1 are like normal osteoblasts, except that their cytoplasm has an ordered granular endoplasmic reticulum, without enlarged cysternae. Moreover, it contains isolated rosettes of glycogen. Cells of Group 2 are like young progenitor cells. There are almost no rough cysternae in the cytoplasm. This contains clusters of glycogen, isolated ribosomes and many mitochondria. Cells of Group 3 are structurally like "resting" flat osteoblasts in normal bone. 3. The paper discusses how the presence of the three groups may be related to vitamin D deficiency or secondary hyperparathyroidism. 4. Malacic osteoid tissue consists of apparently normal collagen fibrils. Both optical and electron microscopy show that this tissue can calcify. But calcification stops at an early stage, or proceeds much more slowly than normal. So large areas ofosteoid tissue are left uncalcified. 5. Calcium salts are laid down either as needle-shaped crystals exactly like those in normal bone, or else abnormally. Where abnormal they either appear in a finely granular, almost amorphous form, or else acquire a characteristic star-like crystalline structure. 6. Where calcification takes place bundles of laterally aggregated collagen fibrils are found

1 . Normal and diseased bone was obtained by biopsy from five patients suffering from Paget's disease. The tissue was studied by histology, microradiography and quantitative fluorescence microscopy using tetracycline markers. Study of the morphological changes showed that two of the biopsies could be regarded as normal, while one was osteoporotic; two biopsy specimens were in the porotic phase of Paget's disease and the remaining five were in the sclerotic phase. 2. The tetracycline markers were used to measure the linear rate at which bone was deposited on individual surfaces (appositional growth rate) in µ per day and the percentage volume of new bone added to the total volume of bone per day (bone formation rate). The values obtained for appositional growth rate in all the biopsies were of the order of 1 µ per day, but slightly higher values were obtained in the diseased tissue of each individual. The bone formation rate in normal bone from the proximal femur was about 0·04 per cent per day, about 0·13 per cent per day in the porotic phase, and about 0·4 per cent per day in the sclerotic phase of Paget's disease. 3. Although these values must be accepted with some reservation, there seems to be no doubt that there is an upper limit of about 1 µ per day to the rate of deposition of bone on an individual bone surface; this suggests that in Paget's disease the osteoblast behaves as a normal cell

1. The syndrome of osteoporosis is reviewed and its various causes are mentioned. Osteoporosis in youngish patients without any demonstrable cause is referred to as "idiopathic." The scant literature on this condition is reviewed. Its clinical, radiological, biochemical and histological features are considered. 2. A series of thirty-eight cases is analysed, and illustrative case histories are described. The peculiarities of the disease as it is seen in women are discussed, particularly the relationship to pregnancy and lactation, which appear to act as precipitating factors, rather than being primarily causative. 3. The differential diagnosis is discussed. Osteogenesis imperfecta may not always be easy to distinguish; since it is really a "congenital osteoporosis" this is hardly surprising. 4. The following possible etiological factors are propounded (apart from pregnancy): nutritional, occupational, lack of sex hormone, liver dysfunction, loss of protein, diabetes, premature ageing, hypophosphatasia, "alarm reaction," and inheritance. None of them can be incriminated except in the odd case. The relationship between osteoporosis and idiopathic hypercalcuria is mentioned. The only conclusion regarding etiology is that some people are simply more prone to bone loss than are others, and in these a variety of accentuating factors may render the disorder clinically apparent. 5. The treatment of the condition is unsatisfactory, although occasionally a positive calcium balance may be obtained with sex hormones or intravenous infusion of plasma albumin or whole plasma. The general tendency seems to be towards clinical improvement (biologically "stabilisation" rather than improvement), but some patients become permanently crippled