We analysed the long-term results of arthrodesis of the shoulder after infection in 15 patients. At the time of operation, 14 cultures were positive for Staphylococcus aureus. The mean follow-up was 8.3 years (3 to 14) and 90% of the patients were satisfied with the outcome. There were complications in five patients (33%); in three there was nonunion with loosening of the implant. One patient had a sound bony union but with a persistent sinus six years after arthrodesis and another had a sinus which healed after the metal was removed. Four of these five patients (80%) were heavy smokers (> 20 cigarettes/day). Cancellous bone grafting did not affect the incidence of complications. The mean age of the patients with complications was 58.6 v 48.6 years for those without (p = 0.2808 ; not significant). Those with complications had had more previous operations (6.4 v 2.5, p < 0.05). Antibiotics, as determined by the bacteriological cultures, were administered for six weeks. The complication rate was higher in patients with active sepsis but the younger the patient and the fewer number of previous operations (< 50 years, < four previous operations), the better was the outcome. Considering the rate of complications, we recommend early surgery in these patients

Migration of 65 Charnley stems implanted with modern cementing techniques was studied by roentgen stereophotogrammetry. There were 25 patients with rheumatoid arthritis (RA) and 40 with osteoarthritis (OA) followed up for two years. In 43 cases a bone sample for histomorphometric analysis was obtained from the femur during the operation. In 22 cases the mean subsidence of the prosthetic head was 0.40 mm and in 20 the mean posterior migration was 1.25 mm. There was no difference in migration between the two diagnostic groups (p = 0.8) after adjusting for variations in gender, age and weight. Male gender was associated with increased subsidence (p = 0.006). Histological examination showed that the RA series had more osteoid surface (p = 0.04), but neither this, nor any of the other histomorphometric variables, influenced migration. These results suggest that, unlike the acetabular socket, the cemented Charnley femoral component is equally secure in osteoarthritis and in rheumatoid arthritis, and that its initial fixation is not influenced by the quality of the local cancellous bone. Our results provide data with which the early performance of new prosthetic designs and fixation methods can be compared

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

The role of three genetically distinct collagen types in the formation of endochondral bone and in calcification and resorption of cartilage has been assessed. Using antibodies specific to types I, II and III collagen we have demonstrated in the embryonic chick tibia that endochondral bone formation began with deposition of type III collagen in lacunae of hypertropic chondrocytes by invading bone-marrow-derived cells. This was followed by the deposition of type I collagen, which is the collagenous constituent of endochondral osteoid. At later stages of development endochondral osteoid was found in the epiphysial growth plate in apparently intact lacunae of hypertrophic chondrocytes; this indicated that the latter might contribute to the synthesis of osteoid type I collagen. Immuno-histological staining for collagen types, and von Kossa staining for calcium phosphate on parallel sections, demonstrated that type I and type II collagen matrices were substrates for calcification. Endochondral bone (with type I collagen) was found on scaffolding of both uncalcified and calcified cartilage (with type II collagen), indicating that calcification of endochondral osteoid and of the underlying cartilage occurred independentyl. Spicules of endochondral cancellous bone of a four-week-old chick contained a core of calcified type II collagen

1. A series of 154 patients who underwent anterior cervical discectomy and fusion has been studied. A detailed analysis of the first eighty-four patients who have been observed for periods of from one to eight and a half years is described. In sixty-eight patients the fusion was done with a keystone type of graft, in seventeen by a dowel (Cloward) graft. 2. Despite a preponderance of multiple level fusions in the keystone series, clinically better results (80·8 per cent excellent or good) were found in this group than in the dowel group (64·8 per cent excellent or good). 3. A biomechanical study has indicated the keystone graft to be more stable than a dowel graft under flexion and extension strains as well as lateral bending strain. The graft is more stable the closer it is to the line of "zero velocity.". 4. The three cases of non-union all occurred in the dowel group. The high incidence of fusion with the keystone technique is considered to be related to the type of graft, its method of seating, its depth of penetration, its larger surface area and the fact that raw cancellous bone of the adjacent vertebral bodies is in contact with the graft above and below

1. The dominant role of pathogenic staphylococci in surgical infections has been confirmed by positive isolations in 89·9 per cent of a wide variety of lesions in a hospital infective unit. Of 150 staphylococci isolated, 147 were sensitive to fusidic acid, two were slightly sensitive and only one was resistant. 2. Fusidic acid was administered as sodium fusidate to 100 patients with staphylococcal infections (including seventy-two with chronic post-traumatic osteomyelitis). Sterile swabs were achieved in seventy-seven of these patients and in the remaining twenty-three a change of flora was detected. 3. Bone samples were taken at operation from twenty-nine patients with chronic osteomyelitis who had been treated for at least five days with fusidic acid. Depending on dosage, the mean fusidic acid concentrations were 7·3 and 9·8 micrograms per gram. Corresponding levels in non-inflammatory bone samples from thirty-one patients were, depending on the duration of treatment, 12·3, 2l·3 and 25·4 micrograms per gram. The fusidic acid levels in cancellous bone were almost twice as high as those in compact bone. 4. The relevance of these findings to the use of fusidic acid therapy as an adjunct to surgical management of chronic osteomyelitis is discussed

1. Methods for culturing cells isolated from slices of arthritic human or normal mammalian cancellous bone are described. 2. The capacity of the cultured cells to take up and hydroxylate labelled proline has been investigated. 3. Sections of the partially decalcified bone and of the isolated cells have been examined by transmission electron microscopy. 4. The possible significance of the results and observations are discussed. We are deeply grateful to Dame Janet Vaughan, who very kindly read this manuscript and made several valuable suggestions and criticisms. We are much obliged to Dr Sylvia Fitton-Jackson for her advice on the techniques of tissue culture and for giving us the composition of her chemically defined medium. Dr Palfrey kindly allowed one of us, M. J. Dickens, to learn transmission electron microscopy in his department at St Thomas's Hospital Medical School under the expert tuition of Mr G. Maxwell. Mr R. Hockhan and Mr M. Hepburn of the University of Surrey Structural Studies Unit helpfully instructed in the operation of the transmission electron microscope. Our special thanks are due to Mr E. P. Morris for his competent and enthusiastic technical assistance

Many analyses of the geometric arrangement of trabeculae in the proximal end of the femur have accepted and perpetuated the theories of Ward (1838), Culmann (1866) and Meyer (1867), and have contributed to the belief that the structure of the femoral neck embodies mechanical principles which are foreign to bony formations elsewhere. This isolated departure from the normal pattern of skeletal behaviour is considered to be most unlikely, and an attempt has been made to show that the structure of the femoral head and neck departs but little from the normal anatomy of the long bone. From a developmental point of view, the proximal end of the human femur is believed, in its simplest interpretation, to represent an upward continuation of the original shaft which has undergone rotation and expansion. The cancellous arrangements of the internal weight-bearing system are likewise believed to represent the expanded and rotated lamellae of the neck as they are presented radiologically or on coronal section. The forces acting upon the proximal end of the femur are considered to be mainly compressive in nature, and both crane and street-lamp bracket theories have therefore been rejected. The spiral conformity of the proximal end of the femur has been related to the spiral disposition of the soft-tissue structures that surround the hip, and in the interpretation of hip joint mechanics the principle of the screw has been preferred to the principle ofthe lever

1. A quantitative study of phosphatase distribution in the limb bones of growing rabbits is reported. 2. Alkaline phosphatase is present in high concentrations in areas of deposition of new bone. Both local concentrations and the total alkaline phosphatase content of a bone are found to decrease with age. There is good correlation between total alkaline phosphatase activity and monthly increment of weight. 3. Acid phosphatase is present in these bones in greatly less concentrations than alkaline phosphatase. 4. The acid phosphatase of bone shows nearly full activity in the presence of 0·5 per cent formaldehyde. It can be subdivided into two enzymes with characteristically different distributions by the effect of M/100 tartrate on activity. 5. The formaldehyde-stable and tartrate-stable acid phosphatase of rabbit bone (FTS) has a distribution very similar to that of alkaline phosphatase, though very much less in amount, and, like the latter, declines in activity as the bone matures. 6. Tartrate-inhibited, formaldehyde-stable acid phosphatase (FSTI) is found mainly in red marrow and cancellous bone, and full activity persists in mature bone. This enzyme may be associated with resorption and remodelling of bone, or it may represent residual activity under these conditions of the acid phosphatase of developing erythrocytes in the marrow

Objectives

MicroRNAs (miRNAs) have been reported as key regulators of bone formation, signalling, and repair. Fracture healing is a proliferative physiological process where the body facilitates the repair of a bone fracture. The aim of our study was to explore the effects of microRNA-186 (miR-186) on fracture healing through the bone morphogenetic protein (BMP) signalling pathway by binding to Smad family member 6 (SMAD6) in a mouse model of femoral fracture.

Aims

Radiostereometric analysis (RSA) studies of vitamin E-doped, highly crosslinked polyethylene (VEPE) liners show low head penetration rates in cementless acetabular components. There is, however, currently no data on cemented VEPE acetabular components in total hip arthroplasty (THA). The aim of this study was to evaluate the safety of a new cemented VEPE component, compared with a conventional polyethylene (PE) component regarding migration, head penetration, and clinical results.

1. Experimental evidence suggests that the autogenous graft exhibits some advantage over refrigerated homogenous grafts in that healing takes place more rapidly but that in the end the results are the same. 2. Histological study of fragments of healing grafts, both autogenous and refrigerated, that have been removed from human hosts shows no significant difference in the rate or method of repair. 3. Study of the clinical results of the use of homogenous transplants in 307 operations shows the bone to be well tolerated. The rate of infection in clean cases was 2·6 per cent; loss of bone occurred in only two cases. 4. Follow-up studies of 248 cases showed successful results obtained in 210, or 85 per cent. These are comparable with the results obtained with autogenous grafts. The healing of cancellous transplants takes place more rapidly than with cortical grafts. Transplants that have been preserved for more than one year do not heal as well as those that have been preserved for a shorter period and the failure rate is higher. 5. The operation of a bone bank is safe and practical. It offers great advantages to the patient and the surgeon from the standpoint of availability, abundance and the elimination of the necessity of secondary operations to obtain bone. When a bone bank is available the number of operations in which bone transplants are used will show a sharp increase

Aims

The diversity of femoral morphology renders femoral component sizing in total hip arthroplasty (THA) challenging. We aimed to determine whether femoral morphology and femoral component filling influence early clinical and radiological outcomes following THA using fully hydroxyapatite (HA)-coated femoral components.

1. Double osteotomy was performed on 1 50 knees between 1961 and 1969. The first fifty-seven cases were assessed independently. 2. The operation of osteotomy of the upper end of the tibia and the lower end of the femur is described. it is emphasised that the osteotomy sites are close to the bone ends and well within the cancellous expansion. 3. The indications for the operation are pain and loss of function in a mobile arthritic knee joint. 4. Flexion of the knee is important during the operation to allow the popliteal artery to be moved away from bone. Arteriograms at necropsy show the danger of damaging the popliteal artery when the knee is extended. 5. The operation appears to be equally effective in osteoarthritis and rheumatoid arthritis. The proliferated synovium of the active rheumatoid knee regresses rapidly following operation. 6. The operation has resulted in relief of pain and increase in function in many knees which had no deformity. When a deformity did exist before operation recurrence of the deformity did not appear to influence the result. 7. The cause of relief of symptoms after osteotomy is not known, and it is suggested that answers to the following questions should be sought: Why are some arthritic knees painful and some not ? Why does physiotherapy relieve pain ? Why does osteotomy relieve pain? Why is double osteotomy followed by regression of synovial proliferation ? Why does osteotomy sometimes fail ? Would osteotomy of one bone (tibia or femur) be sufficient?

1. A study is reported of 190 femora in 174 patients in whom self-curing acrylic cement had been present in the medullary cavity of the upper end of the femur for the fixation of an endoprosthesis for an average period of four years. 2. The bone remained radiologically normal in 81 per cent of cases. 3. Improvement in the thickness of the cortex from pre-existing atrophy was noted in 2·6 per cent. 4. In 4·7 per cent the bone showed some atrophy after insertion of the cement. This exceeded 10 per cent in only two cases. All were originally osteoporotic from polyarthritis; all were satisfactory as regards the arthroplasty itself, and the atrophy could usually be explained by disuse resulting from the state of the opposite lower extremity, or the knee on the same side. 5. In 9·4 per cent there was fusiform hypertrophy of the femoral cortex, the bony texture remaining normal. This appearance was considered physiological and benign. 6. In 2·2 per cent there were changes for which the most likely explanation is chronic non-suppurative osteitis, though no collateral evidence of infection was found. 7. In 44·8 per cent there was a thin line of condensation in the cancellous bone demarcating the outer limits of the cement. This is considered to be physiological and not to indicate failure of immobilisation. 8. In 37·2 per cent there was slight resorption of the cut surface of the calcar femorale. This is considered to be physiological and to confirm the efficacy of weight transmission by cement lower down in the medullary cavity

One hundred and sixty-four cases of intramedullary nailing of the long bones have been studied with special reference to the difficulties and complications encountered. There was one death not attributable to the method. Two cases of pulmonal fat embolism and one case of thrombosis occurred, all in fractures of the femur. The lessons we have learned from our mistakes can be summarised as follows:. 1 . The method requires technical experience and knowledge and is not suited to inexperienced surgeons or surgeons with little fracture material at their disposal. 2. Intramedullary nailing should only be used in fractures to which the method is suited. In general, comminuted fractures or fractures near a joint are unsuitable. 3. Open reduction is preferable to closed methods. 4. The nail should never be driven in with violence. It should be removed and replaced with a new one if difficulty is encountered when inserting it. 5. In fractures of the femur the nail should be driven in from the tip of the trochanter after careful determination of the direction. 6. The nail should be introduced only to the level of the fracture before exploring and reducing the fracture. 7. Distraction of the fragments must be avoided. 8. If the nail bends it should be replaced by a new one, at least in femoral fractures. 9. If union is delayed, the fracture should be explored and chip grafts of cancellous bone placed around it. 10. Improvised nails or nails which are not made of absolutely reliable material should never be used. 11 . Make sure that the nail is equipped with an extraction hole for removal

Aims

The aim of this study is to evaluate the clinical results of operative intervention for femoral metastases which were selected based on expected survival and to discuss appropriate surgical strategies.

Cadaveric knees replaced with the Geomedic, ICLH, Marmor and Total Condylar prostheses were tested in axial compression, in rotation and in hyperextension in order to observe the strength of fixation of the tibial components. In axial compression the strengths at failure varied widely, both with any one prosthesis and between prostheses. This is attributed largely to the strength of the cancellous bone of the tibia, which was measured in each case and also varied widely. Three natural knees failed at loads of 7300, 7600 and 8300 newtons respectively, whereas the strengths of replaced knees ranged from 3000 to 15750 newtons. At least one example of each design failed at less than 7300 newtons, suggesting little or no reserve of strength. The strength of fixation was greater when the tibial prosthesis was large enough to rest on the whole cross-section of the tibia. In rotation the three prostheses embodying rollers in troughs were stiffer than the Marmor which had a nearly flat tibial-bearing surface. The presence or absence of the cruciate ligaments had a negligible effect on torsional stiffness. In hyperextension, knees replaced with the ICLH, Marmor and Total Condylar prostheses failed by rupture of the posterior capsule at moments of about 60 newton-metres, compared with about 100 for natural knees. With the Marmor prosthesis the anterior cruciate ligament was avulsed at about 20 newton-metres compared with about 75 in natural knees, suggesting that in this respect the retention of the cruciate ligaments contributes little. None of the four knees tested after inserting a Geomedic prosthesis showed strengths as high as those replaced with the other three designs

1. In fifteen patients with unilateral osteoarthritis of the hip bilateral measurements of the intraosseous pressure of the femoral neck and determination of femoral vein pressure were done simultaneously. These pressure examinations were followed by bilateral intraosseous phlebography of the proximal part of the femur. 2. In a second series of fifteen patients the intraosseous pressures of the femoral head and neck were measured simultaneously before operation for osteoarthritis. 3. The pressure in the femoral vein was equal on the two sides. The intraosseous pressure in the femoral neck was always higher in the arthritic hip than on the unaffected side. In hips with osteoarthritis the pressure in the femoral head was higher than the pressure in the neck. 4. Intraosseous phlebography indicated a state of intramedullary venous engorgement in osteoarthritis. The normal channels for venous drainage from the femoral head and neck were not visible in the phlebographs from the arthritic side. Instead, drainage took place through descending intramedullary vessels to the trochanteric region and down into the femoral shaft. The emptying of intraosseous contrast material from the arthritic hip was delayed. 5. The phlebographs indicated that the abnormally high intraosseous pressure observed in osteoarthritis is caused by a high resistance to flow across the cortex of the proximal part of the femur. 6. The aching rest pain typical of severe osteoarthritis was noted only in patients with intraosseous femoral neck pressure above 40 millimetres of mercury, an indication that this type of pain is caused by intramedullary hypertension. The decrease of arteriovenous pressure difference, caused by increase of resistance to venous outflow, is probably accompanied by disturbances of nutritive flow. This "venous ischaemia" may play an important role for the structural changes of cancellous bone in osteoarthritis