Aims

The purpose of this study was to compare clinical results, long-term survival, and complication rates of stemless shoulder prosthesis with stemmed anatomical shoulder prostheses for treatment of osteoarthritis and to analyze radiological bone changes around the implants during follow-up.

Aims

Robotic-assisted total knee arthroplasty (RA-TKA) is theoretically more accurate for component positioning than TKA performed with mechanical instruments (M-TKA). Furthermore, the ability to incorporate soft-tissue laxity data into the plan prior to bone resection should reduce variability between the planned polyethylene thickness and the final implanted polyethylene. The purpose of this study was to compare accuracy to plan for component positioning and precision, as demonstrated by deviation from plan for polyethylene insert thickness in measured-resection RA-TKA versus M-TKA.

This paper describes the preliminary results of a proximal tibial endoprosthesis which spares the knee joint and enables retention of the natural articulation by replacing part of the tibial metaphysis and diaphysis. In eight patients who had a primary malignant bone tumour of the proximal tibia, the distal stem, which had a hydroxyapatite-coated collar to improve fixation, was cemented into the medullary canal. The proximal end had hydroxyapatite-coated extracortical plates which were secured to the remaining proximal tibial metaphysis using cortical screws. The mean age of the patients at operation was 28.9 years (8 to 43) and the mean follow-up was for 35 months (4 to 48). The mean Musculoskeletal Tumour Society score was 79% (57% to 90%), the mean Oxford Knee score was 40 points of 48 (36 to 46) and the mean knee flexion was 112° (100° to 120°). In one patient, revision to a below-knee amputation through the prosthesis was required because of recurrence of the tumour. Another patient sustained a periprosthetic fracture which healed with a painful malunion. This was revised to a further endoprosthesis which replaced the knee. In the remaining six patients the prosthesis allowed preservation of the knee joint with good function and no early evidence of loosening. Further follow-up is required to assess the longevity of these prostheses

Aims

The processes linking long-term bisphosphonate treatment to atypical fracture remain elusive. To establish a means of exploring this link, we have examined how long-term bisphosphonate treatment with prior ovariectomy modifies femur fracture behaviour and tibia mass and shape in murine bones.

1. Twenty-eight cases of the infantile and three cases of the adolescent type of tibia vara occurring in West Indian Negroes are reported. 2. The condition is characterised by failure of growth of the postero-medial part of the upper tibial epiphysis. 3. The deformity produced is acute varus at the upper tibia with medial torsion and eventually flexion of the diaphysis on the epiphysis. 4. These deformities are considered to be due to a vicious circle set up by considerable alteration of the lines of force on the medial portion of the upper tibial epiphysial line

Aims

The aim of this study was to determine whether fixation, as opposed to revision arthroplasty, can be safely used to treat reducible Vancouver B type fractures in association with a cemented collarless polished tapered femoral stem (the Exeter).

We examined specimens of hydroxyapatite-coated femoral prostheses from four patients who had died within nine months of implantation for fractured neck of femur. Histology showed newly formed immature bone overlying the hydroxyapatite coating with new trabeculae bridging to the endosteal bone layer. In the diaphysis, where there had been contact between the hydroxyapatite and the cortex, there was dense, firmly anchored bone with an haversian architecture. In other places the newly formed bone had a trabecular structure, containing bone marrow tissue with normal cellularity. It appeared that biological osseointegration had taken place

Growth at the proximal tibial epiphyseal plate of the rat has been measured following three different growth-stimulating procedures. These were proximal periosteal release, distal periosteal release and full periosteal stripping of the diaphysis. A new radiographic method using a photographic technique has made it possible to take accurate measurements of the rate of long-bone growth in small experimental animals. From the results of this animal series we conclude that proximal tibial periosteal division is likely to be the most effective of the three procedures when used to correct leg-length discrepancy in the growing child

Forty-four rabbits were operated on when five weeks old; in one group a 2 mm drill-hole was made in the intercondylar portion of the right femur across the central portion of the growth plate up to the diaphysis, while in the other group a similar drill-hole of 3.2 mm was made. At 3, 6, 12 and 24 weeks after operation, specimens from the growth plates of both femora were analysed using radiographic, microradiographic, histological and histomorphometric techniques. It was found that destruction of 7% of the cross-sectional area of the growth plate caused permanent growth disturbance and shortening of the femur

1. Discs of bone from two fixed sites on the front of the femur were taken from ninety-one necropsy subjects and the density, width and histological appearance of the cortical bone were examined. 2. Cortical thickness, and the density of the femoralcortex, decreased with increasingage of bone. 3. There was an increase in the rate of resorption of the bone cortex from both sexes after the fifth decade. 4. The difference between the density of the metaphysial cortex and that from the diaphysis increased for both sexes after the age of fifty, because of the greater metaphysial resorption. 5. There was no change in the degree of mineralisation of the cortical bone with age. The decrease in density with age is, therefore, accounted for by resorption

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

1. An apparatus was designed to determine the shearing strength of the upper tibial epiphysis in the rat. Observations were made with this instrumenton normal animals, on animals receiving growth-hormone, and on animals receiving oestrogen. 2. When the epiphysis separates from the diaphysis, the plane of cleavage is constant, passing through the third layer of the epiphysial plate. 3. Growth-hormone decreases and sex-hormone increases the shearing strength of the epiphysial plate. These changes are due to alterations produced by these two hormones in the thickness of the third layer of the epiphysial plate. 4. It is suggested that these findings may be of significance in providing an anatomical basis for slipping of the upper femoral epiphysis in man, especially when it is associated with the adiposo-genital syndrome or with rapid adolescent growth

We used the Ilizarov circular external fixator to treat 16 patients with persistent nonunion of the diaphysis of the humerus despite surgical treatment. All patients had pain and severe functional impairment of the affected arm. In ten, nonunion followed intramedullary nailing. We successfully treated these by a closed technique. The nail was left in place and the fracture compressed over it. The fractures of the other six patients had previously been fixed by various methods. We explored these nonunions, removed the fixation devices and excised fibrous tissue and dead bone before stabilising with the Ilizarov fixator. In five patients union was achieved. Bone grafting was not required. In the single patient in whom treatment failed, there had been a severely comminuted open fracture. All except one patient had reduction of pain, and all reported an improvement in function

Malunion of fractures of the forearm in children can lead to permanent disability. The capacity of the radius and ulna to remodel spontaneously after malunion has been assessed in this study. Forty-nine children who had malunited fractures of the forearm were examined when the remodelling process was complete. It was noted that fractures of the distal third of the radius and ulna led to fewer problems than those of the diaphysis. It was concluded that malunion of the distal third of the radius and the ulna will remodel satisfactorily providing the child is less than 14 years of age. Gross malunion of the midshaft of the radius and ulna will spontaneously correct in an infant but little useful correction of deformity can be anticipated in diaphysial fractures when the child is aged eight years or more

In order to study the effect of pure torsional forces upon the rotational development of the growing tibia, 35 immature rabbits underwent torsional loading of one tibia in vivo with a spring-loaded cylinder while the other tibia was a control. The radiographic results showed rotation occurring only at the epiphysial plate. Histologically this was assocaited with angulation of the hypertrophic cartilage columns occurring as little as 24 hours after loading which with longer periods of loading produced angled primary and secondary trabeculae. Radiographic and histological analyses of the diaphysis using tetracycline labelling and Spalteholtz injection techniques failed to show any evidence of cortical remodelling or reorientation of the cortical vessels of a rotational nature, suggesting that rotational modelling occurs solely at the epiphysial plate

Aims

Conservative treatment of moderately displaced proximal humeral head fractures yields good clinical results, but secondary fragment displacement may occur. Identification of those fractures at risk of displacement may influence initial decision-making.

The tibial nutrient artery supplies 62% of cortical blood flow in the diaphysis and normal blood flow is centrifugal (Willans 1987). Intramedullary reaming destroys the nutrient artery and injures the endosteal surface of the cortex. Trueta (1974) suggested that the direction of blood flow can reverse from centrifugal to centripetal after loss of the endosteal supply. We examined this hypothesis by measuring cortical and periosteal blood flow after intramedullary reaming of the tibia in eight sheep, using 57Co radiolabelled microspheres. The unreamed contralateral tibiae served as a control group. Thirty minutes after reaming there was no significant change in cortical blood flow, but a sixfold increase in the periosteal flow. Our study confirms Trueta's hypothesis; after trauma or in other pathological states, flow can become centripetal

Between 1990 and 1998 we saw 21 children with primary subacute haematogenous osteomyelitis. Pain, swelling and a limp had been present for two to 12 weeks with little functional impairment. Laboratory tests were non-contributory. The lesions were classified radiologically into metaphyseal, diaphyseal, epiphyseal and vertebral. There were 24 sites involved, with most (20) being in the tibia; 17 lesions were in the diaphysis, five in the metaphysis and two in the epiphysis. The diagnosis was confirmed histologically in all cases. Staphylococcus aureus was cultured in six patients. Healing occurred in all patients after treatment with antibiotics for six weeks and radiological improvement was seen after three to six months. Subacute osteomyelitis develops as a result of increased host resistance and decreased bacterial virulence. The radiological features can mimic various benign or malignant bone tumours and non-pyogenic infections. Histological confirmation is necessary to avoid a delay in diagnosis

We have reviewed the results in 37 patients with unilateral congenital short femur (Pappas classes III to IX), treated by different lengthening procedures. The increase in the length of the femur varied from 15.6% to 142%, excellent or good results being obtained in 32 patients (86%). There was an average of 1.9 complications per case, most being seen earlier in the series when the Wagner technique was used. With the Orthofix and the Ilizarov techniques, we used callus distraction in all cases. We found that the proximal diaphysis of the congenitally abnormal femur healed less well, and we now prefer to perform corticotomy and callus distraction of the distal metaphysis. The Ilizarov method gave the best results, offering the possibilities of the simultaneous use of a Hoffmann fixator across the hip and the treatment of knee dislocation and instability