There is an urgent need for the staged, controlled, introduction of new technology and new procedures to surgery. A classification system in four stages is proposed, which would allow for prospective assessment of new devices or methods before they are released for use by the surgical community. The proposal recognises the unique nature of a surgical operation and its learning curve. The issues of randomisation and of informed consent are discussed, and are shown not to be barriers to clinical trials, but necessary adjuncts to orderly testing. The importance of continued surveillance of innovations is emphasised.

The results are reported of an audit of allografts collected in the first 18 months of the Leicester Bone Bank. We retrieved 161 femoral heads at primary arthroplasty of which 103 were implanted into 59 patients. There were deep infections in two recipients and wound infections in five. In two of these cases, culture of the femoral head at implantation was positive but the organisms grown were not those which caused the clinical infection. We retrieved 22 large allografts from six cadavers. Four of these were contaminated at retrieval and required irradiation for sterilisation. There has been one clinical infection in the nine large allografts implanted so far. We recommend that all bone banks undertake prospective audit to ensure that high standards are maintained and wastage minimised.

We studied the quantity and rate of formation of new bone during lengthening of 17 limb segments in 10 patients using dual-energy X-ray absorptiometry (DEXA), ultrasonography and radiography. Whereas new bone was detected by both DEXA and ultrasonography within 1 to 2 weeks of distraction, it was not visible on the radiographs until 4 to 8 weeks. Limb alignment and gap measurement were accurately assessed by DEXA without the need for standard radiographs or scanograms. With ultrasound the distraction gap appeared as an echolucent window which narrowed progressively producing a hyper-reflecting line after which further consolidation could not be assessed. As measured by DEXA the density of the new bone at this stage was approximately 45% of control values and did not represent normal cortication. Whereas ultrasound could be used to identify defects in mineralisation and to determine when to dynamise the fixator system, DEXA could measure the quantity and rate of formation of bone throughout lengthening.

We used MRI to examine the hips of 32 asymptomatic patients at 9 to 21 months after renal transplantation covered by high-dose corticosteroids. Five hips in three patients showed changes which indicate avascular necrosis, although radiographs, CT scans and isotope scans were normal. These patients had repeat MRI scans after another two years and three years. One patient with bilateral MRI changes developed symptoms and abnormal radiographs and CT and isotope scans in one hip nine months after the abnormal MRI. Intraosseous pressure was found to be raised in both hips, and core biopsies revealed necrotic bone on both sides. The other three hips have remained asymptomatic with unchanged MRI appearances three years after the initial MRI. It seems that idiopathic avascular necrosis does not always progress to bone collapse in the medium term.

Septic arthritis has been regarded as rare in haemophiliacs, but its incidence may have increased since HIV infection has become widespread in these patients. We describe six cases treated at one haemophilia unit over a two-year period and discuss their investigation, diagnosis and treatment. Four of the patients were seropositive to anti-HIV.

We report the results of imaging with labelled white cells in 52 patients before the revision of 54 cemented joint prostheses at which the diagnosis of infection was made from biopsies. Twenty-five hips were imaged with 111In-oxine-labelled cells; 20 hips and 11 knees were imaged with 99mTc-hexamethylpropylene-amineoxime-labelled cells. Of these, 13 hips and five knees proved to be infected. The scans taken together had an accuracy of 82%, a sensitivity of 44% and a specificity of 100%. Indium scans gave 37% sensitivity, 99mTc labelling 50% sensitivity. Infected arthroplasties with positive scans had presented significantly earlier than those with negative scans, the time after the original insertion being 1.1 years for the true-positive scans and 6.1 years for the false-negative scans. The value of labelled white-cell scans in the detection of infection in failed joint replacements is dependent on the activity of the infection. There is reduced sensitivity to the more insidious infections which affect arthroplasties and aspiration under controlled conditions remains an important investigation.

We treated 37 patients with chronic osteomyelitis of the tibia (25), femur (9), radius (2) and humerus (1) by a two-stage technique, comprising radical debridement of all infected bone and soft tissue with the provision of soft-tissue cover, and delayed autogenous bone grafting when necessary. All patients were reviewed at an average of 49 months (12 to 121). Infection-free bone union was achieved in 34. No patient required amputation. Wide excision of all compromised tissue and the closure of bone within a healthy vascularised soft-tissue envelope are essential if infection is to be eradicated. The combined assessment and management of such patients by an orthopaedic surgeon and a plastic surgeon are advocated.

In a prospective, consecutive study we determined the frequency of common symptoms and signs in 300 patients with lumbar nerve-root compression syndromes. We compared 100 patients with disc herniation (mean age 43 years), 100 with lataral spinal stenosis (41 years) and 100 with central spinal stenosis (65 years), using a standard protocol of common signs and symptoms. The diagnoses were established by one or more of myelography, CT, MRI and nerve-root block, and all were confirmed at operation. The preoperative duration of symptoms was significantly shorter in patients with disc herniation. Pain at rest, at night, and on coughing was as common in lateral stenosis as in disc herniation, but regular consumption of analgesics was more common in patients with disc herniation. Positive straight-leg-raising tests were more common in disc herniation than in lateral stenosis and were uncommon in central stenosis. Motor disturbances were seen most often in central spinal stenosis, especially patellar reflex changes. Sensory disturbances were most common in patients with complete disc herniation.

We assigned 67 patients with central lumbar stenosis alternately to either multiple laminotomy or total laminectomy. The protocol, however, allowed multiple laminotomy to be changed to total laminectomy if it was thought that the former procedure might not give adequate neural decompression. There were therefore three treatment groups: group I consisting of 26 patients submitted to multiple laminotomy; group II, 9 patients scheduled for laminotomy but submitted to laminectomy; and group III, 32 patients scheduled for, and submitted to, laminectomy. The mean follow-up was 3.7 years. Bilateral laminotomy at two or three levels required a longer mean operating time than total laminectomy at an equal number of levels. The mean blood loss at surgery and the clinical results did not differ in the three groups. The mean subjective improvement score for low back pain was higher in group I but there was also a higher incidence of neural complications in this group. No patient in group I had postoperative vertebral instability, whereas this occurred in three patients in groups II and III, who had lumbar scoliosis or degenerative spondylolisthesis preoperatively. Multiple laminotomy is recommended for all patients with developmental stenosis and for those with mild to moderate degenerative stenosis or degenerative spondylolisthesis. Total laminectomy is to be preferred for patients with severe degenerative stenosis or marked degenerative spondylolisthesis.

We have reviewed 31 consecutive patients, aged 65 years or more, after surgical decompression for degenerative lumbar spinal stenosis. The average follow-up was 42 months. Assessment included a standard questionnaire, a pain diagram which was completed by the patient, and clinical and radiological examination. Patients were considered in three groups; degenerative spondylolisthesis (19), lateral recess stenosis (5), and central-mixed stenosis (7). The indication for surgery was leg pain: no patient had an operation for back pain alone. Fusion was never performed. Overall, 64% of the patients had an excellent result, 17% a good result and 19% a poor result. We conclude that the long-term outcome of decompressive surgery in the elderly is good; it does not differ from that reported for younger patients.

Fast bowling in the game of cricket requires repetitive spinal extension, lateral deviation, lumbar flexion and thoracodorsal rotation. Back pain is common, and it has been shown that pars interarticularis defects had occurred in over 50% of a group of teenage fast bowlers. Many of these defects will heal, but some cause chronic pain which prevents bowling, although other activities may be painless. We report the successful results of local screw fusion of the pars interarticularis defects in ten bowlers, and recommend this method for this small group of sportsmen.

We have studied the case records of 16 patients with dislocations of the cervical spine who deteriorated neurologically during or after reduction. The dislocations were reduced by skull traction in four patients, by manipulation in four and by operation in seven. This complication was not related to age, sex, mechanism of injury, or the level and the type of dislocation. Fourteen patients made substantial recoveries, one made a partial recovery and one patient remained totally paralysed and died three months later. The causes and prevention of spinal-cord damage at this stage of management are discussed, and the early use of MRI or CT myelography is recommended.

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.

We compared two treatments for tears of the rotator cuff of 1 to 4 cm in size. One group of 22 patients had an arthroscopic subacromial decompression and rotator-cuff debridement; the other comparable group of 23 patients had open repair and acromioplasty. Review was at 2 to 5 years postoperatively. Both groups had similar pain relief and range of active forward flexion, with significant improvement from the preoperative condition. The open repair group scored better for function, strength and overall score, but patient satisfaction was similar in the two groups. We recommend the use of arthroscopic subacromial decompression and debridement for low-demand patients who require mainly pain relief and range of movement. Open repair is necessary if strength and functional recovery are the prime objectives.

We used ultrasonography in ten children with pulled elbow to compare measurements of the radiocapitellar distance (RCD) on the affected and the unaffected sides. Similar measurements were made in a group of ten age-matched normal children. The mean RCD in pronation of the affected and normal sides in the patients with pulled elbows was 7.2 mm +/- 0.7 and 3.8 mm +/- 0.5, respectively (p < 0.0001). In the normal children the mean RCD in pronation was 4.5 mm +/- 0.5. We conclude that ultrasonography is of value for documenting pulled elbow in children.

Fracture of the tuberosity of the scaphoid is common and usually heals without incident because of the good blood supply. We report four cases of nonunion of this fracture. Three of them were symptomatic and two required operative treatment.

We compared the results in two groups of patients with late reduction of posterior elbow dislocations, one of which had lengthening of the triceps (group A, n = 36) and the other did not (group B, n = 34). The elbows had all been dislocated for more than one month and less than three months. The patients in group B had better clinical results and significantly less postoperative flexion contracture (p < 0.05).

We report eight patients with prominent cystic changes in the head of the fibula. Seven of these had osteoarthritis of the adjacent knee, and five had evidence of local deposition of calcium pyrophosphate dihydrate crystals. A radiographic survey of 470 knees in 254 patients with osteoarthritis suggested that such cysts are rare, but should be considered in the differential diagnosis of such changes before expensive or invasive investigations are performed.

Seven subjects with normal joints were tested for active and passive position sense of ankle inversion, peroneal reflex reaction time to sudden ankle inversion, and postural stability during single-leg stance. The tests were performed before and after regional block of the ankle and foot with local anaesthetic. Passive position sense, assessed with the muscles relaxed, was greatly impaired by anaesthesia but active position sense, with the calf muscles activated, was preserved, and the peroneal reaction time to sudden ankle inversion was not altered. The magnitude of postural sway during single-leg stance was also unchanged by anaesthesia of the ankle and foot. The results suggest that the afferent input from intact lateral ankle ligaments is important in sensing correct placement of the foot at heel-strike, but that this input can be replaced by afferent information from active calf muscles. Afferent input from these muscles seems also to be responsible for dynamic ankle protection against sudden ankle inversion and is adequate to allow stable single-leg stance.

We reviewed 17 patients after arthroscopic resection for anterior impingement in the ankle. All had had painful limitation of dorsiflexion which had failed to respond to conservative treatment. Review at an average of 39 months showed very significant improvements in levels of pain, swelling, stiffness, limping and activity. There was a significant improvement in the range of dorsiflexion but not of plantar flexion. One poor result was due to a superficial infection, and two other patients had residual numbness of the foot which persisted for several months.

We have studied the incidence of fractures of the proximal femur in one English county from 1968 to 1991. Numbers have increased steadily, but the age-specific incidence has remained relatively unchanged since 1981. The increase is due to the rise in the population most at risk; this is likely to continue causing a 20% increase in demand for treatment by the year 2000. Suitable allocation of resources must be planned.

We conducted a prospective randomised trial to compare the results of anatomical reduction and medial displacement osteotomy in 127 consecutive patients with unstable intertrochanteric fractures, of whom 109 completed the study. After an average follow-up of 11 months, we found no significant differences in walking ability, social status or failure of fixation in the two groups. Postoperative complication rates and the early mortality rate were not significantly different, but operating time and blood loss were significantly higher in the osteotomy group. With the use of modern sliding hip screws, medial displacement osteotomy is rarely indicated for unstable intertrochanteric fractures.

Screw devices used to treat fractures of the femoral neck are usually positioned under image-intensifier control, using anteroposterior and lateral views. The volume projected by these views is over 27% larger than the femoral head; the tips of screws so placed may be outside the femoral head. This can be avoided by placement within the central two-thirds of the head: we have designed a template which can confirm safe placement.

We made a prospective study of the incidence and natural history of algodystrophy and associated changes in bone mineral density in the ankles and feet of 60 consecutive patients who had suffered unilateral fractures of the tibial shaft. At bone union, 18 patients showed signs of algodystrophy. Its development was independent of the type of fracture management and of the severity of injury. Patients with algodystrophy lost significantly more bone mineral than did those without but the degree of this loss was independent of the type of treatment and of the time to fracture union. In most cases the symptoms resolved within six months of fracture union but in four patients they were still present at one year and two of these had not returned to work.

We reviewed 68 fractures of the distal radius in children, all treated by primary manipulation and plaster immobilisation. Complete displacement of the fracture and failure to achieve a perfect reduction were both associated with a significant increase in the chance of redisplacement. We recommend the use of percutaneous Kirschner wires to maintain a satisfactory position in all cases in which a perfect reduction cannot be achieved.

We studied the histology of the cement-bone interface and the regenerated synovium in ten aseptically loosened arthroplasties in rheumatoid patients. In two patients we found rheumatoid nodules at the cement-bone interface and marked lymphoplasmacytic infiltration in another three. Failed joints in osteoarthritic patients did not show these changes, and it seems likely that the presence of abundant immunocompetent cells was due to the background disease. We speculate that rheumatoid inflammation contributed to the process of loosening.

We studied the effects of nine techniques of bone surface preparation on cement penetration and shear strength at the cement-bone interface in a standard model of bovine cancellous bone. In unprepared bone the mean penetration was 0.2 mm and the mean shear strength of the interface was 1.9 MPa, less than that of the underlying bone. Brushing with surface irrigation gave mean penetrations of 0.6 to 1.4 mm and mean shear strengths of 1.5 to 9.9 MPa. In 50% of specimens the interface was weaker than the underlying bone. The use of pressurised lavage resulted in mean penetrations of 4.8 to 7.9 mm and mean shear strengths of 26.5 to 36.1 MPa, which were greater than those of the cancellous bone in all specimens. Pressurised lavage was equally effective alone or in combination with brushing, and its efficacy was not altered by using pulsed or continuous jets, or by changing the temperature of the solution from 21 degrees C to 37 degrees C.

A flanged socket was introduced by Sir John Charnley for use in his low-friction hip arthroplasty in 1976. Experimental evidence has suggested that the flange offers an advantage in terms of cement pressurisation at the time of implantation. We have reviewed 302 primary Charnley arthroplasties followed for 9 to 11 years to determine the effect of the flanged socket on the radiological appearance. The incidence of radiological demarcation at the cement-bone interface is significantly reduced in early radiographs after the use of a flanged socket, and the advantage is maintained in the long-term results.

In acetabular dysplasia, fixation of the acetabular component of a cemented total hip prosthesis may be insecure and superolateral bone grafts are often used to augment the acetabular roof. We used finite element analysis to study the mechanical importance of the lateral acetabular roof and found that the lateral acetabular rim plays an important role in the load transfer of the pelvic bone. When the superlateral rim was lacking, the load shifted to the posterosuperior rim and to the area of pubic support, and the stresses in all materials, especially in the cement and in the trabecular bone, increased greatly. At the cement-bone interface the tilting component of the shear stress increased threefold. In a model in which the dysplastic acetabulum was augmented by a rigidly fixed, load-transmitting bone graft, the stresses were considerably diminished.

We reviewed the plain radiographs, bone scans and hip aspiration results of 54 patients with painful hip arthroplasties which had been explored surgically, to compare the results of the investigations with the operative findings. For acetabular loosening, the sensitivity and specificity of bone scanning were 87% and 95%, with an accuracy of 90%: for serial plain radiography sensitivity was 95%, specificity 100% and accuracy 97%. For femoral component loosening, bone scan sensitivity was 85%, specificity 100% and accuracy 89%: the sensitivity of plain radiography was 100%, with specificity 92% and accuracy 98%. Technetium bone scanning did not provide additional information with regard to loosening and is not necessary in the routine investigation of a painful hip arthroplasty. Serial pain radiography is the most effective method of detecting loosening, and bone scanning is useful only when radiography is inconclusive with regard to loosening or infection.

Ultrasound scans were made of the hips of 209 neonates born consecutively over a two-week period. Of the 418 scans, 62 images were selected at random and 25 of these were duplicated to give a total of 87 scans. These static images were then presented to five experienced observers who each made nine different assessments and measurements. Interobserver and intraboserver agreement was calculated and expressed as kappa values. Our results showed poor reliability on both counts.

Sixty-nine hips in 62 patients were treated by the Pavlik harness for congenital dislocation. Ultrasonography showed three degrees of residual head displacement when the harness was first applied. In type A, the femoral head showed contact with the inner posterior wall of the acetabulum. In type B, it contacted the posterior margin of the socket, with its centre at or anterior to the acetabular rim. In type C, the femoral head was displaced outside the socket, with its centre posterior to the acetabular rim. All 51 hips with type A displacement remained reduced. Of nine hips of type B, five were reduced, but the other four were not. None of the nine hips with type C dislocation became reduced with continued use of the harness. The Pavlik harness is indicated for type A and some type B dislocations, but the latter need daily ultrasound monitoring, with a change in method of treatment if type C displacement appears or if the hip is not reduced within one or two weeks. Treatment by Pavlik harness is not indicated in hips with type C dislocations.

We assessed the outcome after simultaneous multiple operations performed on 18 children with spastic diplegia, with emphasis on the changes in the physiological cost index (PCI) of walking. Fourteen patients had a measurable reduction at one year, but the more severely affected patients took up to two years to reach a new functional plateau. The level of the preoperative PCI allows prediction of the outcome of surgery in terms of reducing the effort of walking, or improving its appearance only. Intrapelvic intramuscular psoas tenotomy produced an improvement of hip flexion deformity in 15 of 17 patients without the loss of muscle power to initiate the swing phase. Fractional lengthening corrected hamstring tightness in 17 cases, and the mean popliteal angle was reduced from 63 degrees preoperatively to 30.2 degrees, with almost complete resolution of the fixed knee flexion deformity present in ten patients. Distal transfer of the rectus femoris, when it was shown to be contracting inappropriately, improved the knee flexion arc during walking from a mean of 28.3 degrees to 45.2 degrees.

We reviewed 20 patients with spina bifida who had had surgical management of tibial torsion. Eight had had bilateral procedures and 12 a unilateral procedure, giving a total of 28 limbs for analysis. We performed closed osteoclasis on seven limbs and tibial osteotomy on 21. In the closed osteoclasis group six limbs (85%) had a good result after an average follow-up of nine years (2 to 22). All limbs developed postoperative anteromedial bowing of the tibia which later remodelled. In the tibial osteotomy group 19 (90%) had a good result. The average follow-up was nine years (2 to 28). Complications occurred in seven limbs (33%). We recommend closed osteoclasis of the tibia for the young patient with spina bifida in whom walking is impeded by excessive internal tibial torsion, and supramalleolar tibial osteotomy in the older patient with excessive external tibial torsion and a planovalgus foot.

We report the results of a new surgical procedure for spastic equinovarus deformity due to cerebral palsy. This is the transfer of the anterior half of the split tibialis posterior to the dorsum of the foot through the interosseous membrane. We performed the operation on 23 feet in 18 children. All patients were assessed before operation and at follow-up at a mean of 8.4 years postoperatively. Using the criteria of Kling et al (1985), excellent results were obtained in 14 feet, good results in eight, and a poor result in only one.