Improved cementing techniques have been shown to decrease the rate of aseptic loosening of femoral components of cemented total hip replacements at five to seven years. We now report our results in 105 hips in 93 patients at 10 to 12.7 years (mean 11.2). The improved techniques included use of a medullary plug, a cement gun, a doughy mix of Simplex P and a collared stem of chrome cobalt. Only three femoral components had definitely loosened, none were probably loose and 24 were graded as possibly loose. In contrast, the incidence of radiographic loosening on the acetabular side was 42%. Improved cementing techniques have produced a marked reduction in the rate of aseptic loosening of the femoral component, but the incidence of acetabular loosening is unchanged.

We made a retrospective study of 55 primary total hip arthroplasties in 53 patients with a history of previous acetabular fracture. The mean follow-up was 7.5 years and the average age at fracture was 48.7 years. The incidence of radiographic femoral loosening (29.4%), symptomatic loosening (15.7%), and femoral revision (7.8%) were similar to those previously reported at 10 years for routine arthroplasties by Stauffer (1982). On the acetabular side, the incidence of radiographic loosening (52.9%), symptomatic loosening (27.5%), and revision (13.7%) were four to five times higher. We conclude that a history of prior acetabular fracture has a significant adverse impact on the long-term outcome of any subsequent total hip arthroplasty.

We assessed the results of Chiari pelvic osteotomy in 64 hips with early osteoarthritis in terms of acetabular labral detachment detected pre-operatively by arthrography. At an average follow-up of four years, assessment by the Merle d'Aubigne score showed 83% excellent or good results. These satisfactory results were achieved in only half the cases with a detached labrum, but in nearly all cases with normal or torn acetabular labra. Other factors such as the acetabular index, the level and angle of osteotomy, and the displacement following osteotomy did not affect the results. Chiari pelvic osteotomy is a worthwhile procedure for early osteoarthritis in selected cases, but a detached acetabular labrum increases the risk of clinical failure.

We measured the blood loss during and after hip replacement in two groups of women, each consisting of 10 patients. In one group the lumbar plexus was infiltrated with bupivacaine, in the other it was not. The group in whom the plexus was blocked had significantly less blood loss.

In a prospective study of 100 knee arthroplasties in patients with rheumatoid arthritis, simultaneous bilateral surgery was compared with staged bilateral replacements. All patients had improved function following their operations but those who had staged surgery only achieved maximum benefit after the second knee had been replaced. The complication rate was no greater for simultaneous surgery and we therefore advocate the method for those patients who require bilateral replacements.

We present a study of 67 Oxford bicompartmental total knee replacements performed at a district general hospital. In this general orthopaedic unit, 57 of the knees (85%) had significant relief of pain with a mean flexion range of 95 degrees and a mean flexion deformity of only 9 degrees. There was a noticeable difference between osteoarthritic and rheumatoid knees. Poor results could be directly related to an avoidable postoperative complication. The results of this independent assessment may be compared favourably with the previously published series from the specialist centre at which the prosthesis was designed.

The incidence of deep vein thrombosis in 244 patients who had total knee replacement has been studied. In 120 the prosthesis was cemented and in 124 it was cementless. In all cases the replacement was primary and a porous-coated prosthesis with a porous-coated central tibial stem was used. Deep vein thrombosis was diagnosed by venography, and pulmonary embolism by perfusion scanning. The incidence of deep vein thrombosis in the cementless knees (23.8%) and in the cemented (25%) was approximately the same. The only significant predisposing factors for deep vein thrombosis in both groups were obesity, prolonged postoperative immobilisation, previous venous disease and hyperlipidaemia.

We studied the rate of revision in 84 consecutive total hip replacements performed for failed osteosynthesis of femoral neck fractures and compared it with that for primary arthroplasty for osteoarthritis. The age and sex adjusted risk of prosthetic failure was 2.5 times higher after failure of fixation, but all the excess risk was in patients over 70 years of age. There were radiographic signs of loosening of the femoral component at five to 12 years after secondary arthroplasty in six of 33 survivors. In general, the results of secondary replacement were no worse than those obtained after primary arthroplasty for femoral neck fracture. We consider that internal fixation should be the primary procedure: total hip replacement is a safe secondary procedure when osteosynthesis fails.

In a 10-year prospective study, 561 displaced subcapital fractures of the femoral neck in 546 patients were treated with the Hastings bipolar hemiarthroplasty. Within six months of their operations, 148 patients had died. In 322 hips followed up, 243 with adequate serial radiographs separated by more than one year, only 14 (5.6%) showed acetabular erosion. A group of 91 had been reviewed for between three and nine years (mean, 4 years 10 months) and of these, 95% had no pain or slight pain only. Comparison with an earlier series of conventional hemiarthroplasties reported from this institution showed that the clinical results were similar, but that the erosion rate had been halved.

We compared, under laboratory conditions, the resistance to cutting out of the AO dynamic hip screw and the Pugh sliding nail. The mean load at cut out, adjusted for bone strength, was 70% greater for the Pugh sliding nail. The reasons for this difference are discussed.

The rigidity of a sliding compression screw and three cannulated lag screws in the treatment of subcapital fractures was compared in five pairs of female cadaver femora. There were no significant differences between the compressive strength, bone density, cortical thickness or Singh index of the bones in each pair. A subcapital fracture was standardised using a perpendicular saw cut across the femoral neck. A uniaxial 'load test system' with force and length measurement facilities was used to mimic cyclical stressing applied in vivo at a frequency of 0.5 Hz from 0 to 3 times body-weight. There was no significant difference between the fixation afforded by the sliding compression screw and three lag screws. Bone quality was the single most important factor in the stability of the bone implant unit.

An analysis of 51 type III open tibial fractures treated by external skeletal fixation is presented. The fractures are subdivided according to the classification of Gustilo, Mendoza and Williams (1984) into types IIIa, IIIb and IIIc. The different prognoses of these fracture subtypes is examined. The use of the Hoffmann and Hughes external fixators in the management of type III open tibial fractures is presented and it is suggested that the prognosis is independent of the type of fixator used.

We analysed the results of 93 tibial shaft fractures treated with the Grosse-Kempf locked nail. Twenty-six fractures were comminuted, 19 were open grade I to II, and 54 were located outside the middle third of the tibia. The deep infection rate was 3.2%. There were only two poor results. The use of this method is recommended and discussed.

Following the discovery of a powerful venous pump in the foot that is activated by weight-bearing independently of muscular action, a pneumatic impulse device was developed to actuate this pump artificially. In a multicentre international trial the device was shown to reduce post-traumatic and postoperative swelling; pain also was alleviated. Evidence is also presented that dangerously high compartment pressures may be reduced to acceptable levels and fasciotomy avoided. We present an explanation of the clinical effects of activation of the venous footpump, based on recent improved understanding of the physiology of the microcirculation. The hyperaemic response that follows the liberation of endothelial-derived relaxing factor (EDRF) by sudden changes of pressure after weight-bearing or impulse compression is particularly important.

The mechanism of the pivot shift was investigated by analysing movements under valgus torque in 29 fresh cadaveric knees. The movements were measured in three dimensions, using biplanar photography, when all the ligaments were intact, and then after the ligaments were sequentially divided. When only the anterior cruciate ligament was sectioned, the pivot shift occurred in seven out of 20 knees examined. In the other 13, though the pivot shift was not observed, an abnormal internal rotation occurred at between 10 degrees and 50 degrees of flexion. Division of the iliotibial tract in addition to division of the anterior cruciate ligament stopped the pivot shift, as the tibia remained internally rotated throughout the range of flexion. The axis of rotation of the pivot shift was located at the medial collateral ligament, which was kept tight by the applied valgus torque. The sudden movement in the pivot shift was caused by a complex interaction between the geometry of the knee and the valgus torque applied.

We studied the precise role of the fracture haematoma in healing by the experimental transplantation of the haematoma at two days and four days after fracture of the rat femur to subperiosteal and intramuscular sites. We used bone marrow and peripheral blood haematomas for control experiments. The transplanted two-day fracture haematoma produced new bone by endochondral ossification at the subperiosteal site, but not at the intramuscular site. Four-day fracture haematoma produced new bone formation at both subperiosteal and intramuscular sites. These results suggest that fracture haematoma has an inherent osteogenetic potential.

Four different experiments were performed to study the healing of a large, non-vascularised, diaphyseal, bone segment in adult cats. In the first experiment, a 4 cm segment of tibia with its periosteum was excised and replaced in its bed. The other experiments were similar, except that in the second, the periosteum of the segment was removed, in the third its medullary canal was blocked with a Silastic rod, and in the last group the segment was isolated from its muscle bed by a Silastic sheet. The reparative processes were quantified by estimating the resorption index, the cortical new bone formation index, the callus encasement index, and the osteocyte count. Bone resorption and apposition occurred in the segment even when the periosteum was absent or the medullary canal was blocked, with osseous union at both ends by eight to 12 weeks, provided the segment was not isolated from its muscle bed. Thus, the muscle bed played a significant role in these reparative processes.

We report our experience in 42 patients, using corticocancellous bone grafts and lag screw fixation for un-united scaphoid fractures. Using a grading system, we analysed the suitability of the method for three types of nonunion. We recommend the operation for the treatment of scaphoid nonunion, except where there is avascular necrosis of the proximal pole.

We report a prospective randomised trial comparing Keller's arthroplasty and arthrodesis of the first metatarsophalangeal joint for the management of symptomatic hallux valgus and hallux rigidus in the older patient. In 81 patients (110 feet), with a minimum of two years follow-up, both procedures gave a similar degree of patient satisfaction and symptom relief. The incidence of metatarsalgia was also similar. As there were no obvious advantages to arthrodesis, and since six out of 50 arthrodesed toes required revision, we suggest that Keller's arthroplasty is the better operation in these patients.

We studied the position and rotational changes associated with elevation of the glenohumeral joint, using a three-dimensional magnetic-field tracking system on nine fresh cadaveric shoulders. The plane of maximal arm elevation was shown to occur 23 degrees anterior to the plane of the scapula. Elevation in any plane anterior to the scapula required external humeral rotation, and maximal elevation was associated with approximately 35 degrees of external humeral rotation. Conversely, internal rotation was necessary for increased elevation posterior to the plane of the scapula. The observed effects of this rotation were to clear the humeral tuberosity from abutting beneath the acromion and to relax the inferior capsular ligamentous constraints. Measurement of the obligatory humeral rotation required for maximal elevation helps to explain the relationship of the limited elevation seen in adhesive capsulitis and after operations which limit external rotation.

Thirty-four neonates with osteomyelitis were reviewed. The hip (19) was the most common site involved. Swelling and pseudoparalysis were the most significant local signs. Radiographic abnormalities, such as metaphyseal rarefaction and/or joint subluxation were found on the initial radiographs in 18 of the 19 hips involved. All patients were treated with antibiotics and all infections involving joints were drained surgically. Good results were achieved in 75% of all sites and in 68% of hips.

We reviewed 15 children with transient synovitis of the hip who had aspiration of an effusion under local anaesthesia with ultrasound guidance. There were no significant complications; aspiration was useful for diagnosis and gave considerable symptomatic relief. We discuss the role of ultrasound in diagnosis and treatment.

We have used a modified technique of cervical osteotomy to treat a consecutive series of 23 patients with chronic slip of the upper femoral epiphysis. It has been successful in correcting both moderate and severe deformities with a low incidence of avascular necrosis, comparable to that seen after subtrochanteric osteotomies. We describe the operative details and discuss the features which make cervical osteotomy technically superior to intertrochanteric and subtrochanteric procedures.

We reviewed 27 patients who had supracondylar closing wedge osteotomy for cubitus varus. There were 10 excellent and 12 good results. However, of these 22 patients, 14 had a significant bony prominence over the lateral condylar region caused by lateral displacement of the elbow when closing the osteotomy. This prominence was less obvious in patients who had their osteotomy at a young age, but worse after operations near or after skeletal maturity. This difference appeared to be due to remodelling.

Asymptomatic cyst-like cortical defects appearing after fractures in children have been occasionally reported. Typically, these defects appear during fracture consolidation, within the newly formed subperiosteal bone, proximal to the fracture line, do not enlarge, and progressively disappear. We have previously shown a fatty density on CT scan within the early cortical defect. We now present two additional cases in which early CT scans appeared to confirm that these transient cortical defects may consist of fat, and probably result from the inclusion of medullary fat within the subperiosteal haematoma.

To study the anatomy of subarticular bone and cartilage, fresh specimens of cartilage on bone from the human shoulder, hip and knee were treated with bleach or papain, or were fixed and decalcified. All were compared using scanning electron microscopy. Papain digestion selectively removed cartilage to the tidemark. The tidemark contour was highly variable; irregularities were indirectly related to degenerative lesions and were most prominent in peripheral non-weight-bearing areas of joints with central fibrillation. Decalcification exposed the interface between the bone and calcified cartilage. Collagen fibrils in articular cartilage did not interdigitate with those of bone. The subchondral bone was appositional, avascular, smooth and very thin in most areas of human joints. Perforations through subchondral bone or calcified cartilage were rare. Bleach maceration destroyed important details.

About 20% of patients with leprosy develop localised granulomatous lesions in peripheral nerves. We report experiments in guinea-pigs in which freeze-thawed autogenous muscle grafts were used for the treatment of such mycobacterial granulomas. Granulomas were induced in guinea-pig tibial nerves and the animals were left for 7 to 100 days in order to assess maximal damage. The local area of nerve damage was then excised and the gap filled with denatured muscle grafts. Clinical assessment after periods up to 150 days showed good sensory and motor recovery which correlated well with the histological findings. The muscle graft technique may be of value for the treatment of chronic nerve lesions in selected cases of leprosy.

We reviewed 21 patients with 22 ruptures of the extensor pollicis longus at a mean of 5.3 years after transfer of the extensor indicis proprius tendon. Of these, 19 with 21 transfers described the result as good, and two as fair. The mean deficit of extension between the operated and unoperated thumbs was 1.4 cm, and the mean flexion deficit 0.6 cm. Pressure gauge measurements showed that the strength of the transfer was 51% of that of the uninjured extensor. The two fair results had an extensor lag of over 1.5 cm. Independent extension of the index was maintained in all patients, none having a discernible lag, but the strength of index extension was reduced to 49% of that of the normal finger. There was no evidence of functional loss. Extensor indicis proprius transfer for rupture of the extensor pollicis longus tendon is a simple and reliable procedure with few complications. It gives satisfactory long-term extension of the thumb.

We describe a method of obtaining a biopsy from the body of a vertebra by an open transpedicular route. This minimises the danger of contamination of tissue planes and spaces.

Posterior spinal instrumentation with the placement of intrapedicular implants has become an important technique. We have designed a hand-held target device to facilitate the open or percutaneous location and penetration of the thoracolumbar pedicles. A cylindrical pin guide incorporates two metal rings and can be moved under image intensifier control until the rings are superimposed to show correct alignment. The radiation dosage for the surgeon is minimal; the device allowed accurate placement of 106 consecutive pedicle screws.

We prepared a prosthesis for the replacement of the lumbar vertebrae of sheep, using apatite- and wollastonite-containing glass-ceramic. The material is stronger than human cortical bone and has the special feature of chemical bonding to bone. Ten sheep underwent replacement of L3 and L4 vertebrae, without bone grafting. The animals were killed at intervals from three months to 27 months after operation, and the interface between the prosthesis and bone was examined radiologically, histologically and crystallographically. Bone bonding with the prosthesis had occurred in half the implants. It took at least one year for bonding to be complete, but an apatite layer on the surface of the prosthesis was observed as early as three months after the operation, suggesting the possibility of much earlier bone bonding if more rigid fixation of the prosthesis had been provided.

The modified Schollner costoplasty is a cosmetic procedure for the correction of rib prominence deformity in scoliosis. We present the results of the procedure in 21 patients who had previously undergone spinal fusion for scoliosis. We found the procedure to be well tolerated without major complications. Objective cosmetic improvement was achieved in all but one case. All but one patient considered the procedure to have been of cosmetic benefit.

We reviewed 43 patients who had sustained soft-tissue injuries of the neck after a mean 10.8 years. Of these, only 12% had recovered completely. Residual symptoms were intrusive in 28% and severe in 12%. Pain in the neck and lower back was the commonest complaint and older patients had a worse prognosis. After two years, symptoms did not alter with further passage of time.

We describe a method for approaching the lower cervical and upper thoracic spine, the brachial plexus and related vessels. The method involves the elevation of the medial corner of the manubrium, the sternoclavicular joint, and the medial half of the clavicle on a pedicle of the sternomastoid muscle. We have used this exposure in 17 cases with few complications and good results. Its successful performance requires high standards of anaesthesia, surgical technique and postoperative care.

We made a retrospective study of 149 children and adolescents with moderate spondylolisthesis (slip less than or equal to 30%), 77 treated by fusion and 72 conservatively at an average follow-up of 13.3 years. Both groups were fully comparable with regard to age at diagnosis, sex distribution (46% girls), and mean slip. The patients who were treated operatively had more pain before treatment and showed more initial progression of the slip. They had better clinical results and less pain at latest review, but the total progression of the slip over the whole follow-up showed no statistical differences between the two groups. Patients with a pseudarthrosis after attempted fusion had had a longer period of postoperative pain, but at the latest review had no more pain than those with sound fusion. None of those treated conservatively came to fusion later and the long-term results in 18 patients who had refused the advised operation were no worse than those for other conservatively treated patients. Our results suggest that a moderate grade of spondylolisthesis in adolescents usually has a benign course. It seems that spontaneous segmental stabilisation occurs as a result of degeneration of the disc at the level of the slip.

We report the cases of teenage twin girls presenting within months of each other with severe symptoms from lumbosacral disc prolapses, requiring laminectomy in one and chemonucleolysis in the other. CT scans showed similarities in spinal configuration, including the presence of disc bulges at the L4-5 level. This suggests a strong hereditary factor in prolapse of intervertebral discs, but a review of the literature showed little information on that aspect.

The pre-operative lumbar spine radiographs of 200 consecutive patients who had undergone discectomy for prolapsed intervertebral disc were reviewed. Prolapse was recognized as bulging or sequestration of the disc with consequent root compromise. Measurement of the lumbar level of the interiliac line was shown to correlate with the level of disc prolapse and the incidence of transitional vertebrae at the lumbosacral junction was significantly higher than normal. A pathological value for the lumbosacral angle could not be identified.