In 1887, Konig claimed that loose bodies in the knee joints of young persons had three causes: (1) very severe trauma; (2) lesser trauma causing contusion and necrosis; and (3) minimal trauma acting on an underlying lesion-for which he suggested the name osteochondritis dissecans. His thesis has stood the test of time. We still confuse the second and third categories but osteochondritis dissecans has been identified as an ossification defect.

The technique and results of microsurgical techniques for lumbar disc protrusions in 60 patients are presented. All patients were followed up for a minimum of 2.5 years, and 91% had good or excellent results. The only patient with a recurrent disc sequestration had a good result after a second operation.

Magnetic resonance imaging (MRI) was used to compare the appearance of the spine in 20 adolescents with proven symptomatic intervertebral disc herniations with that in 20 asymptomatic patients who acted as controls. Abnormality in the signal from the nucleus pulposus of one or more discs was present in all patients, while only four of the 20 controls had any abnormal signals. In all the patients the symptomatic disc produced an abnormal signal and in most a herniated fragment of the nucleus pulposus was identified. Fifteen of the 20 patients had multiple-disc abnormality: six had three abnormal discs and nine had two. This suggests there was an underlying diathesis in patients who later developed disc herniation.

Of a total of 905 patients with fracture or fracture-dislocation of the thoracolumbar spine admitted from 1969 to 1982, a neurological deficit was present in 334 (37%). All unstable injuries were initially treated by reduction and posterior fusion. In 79 of these patients, an anterolateral decompression was undertaken later because of persistent neurological deficit and radiographic demonstration of encroachment on the spinal canal. One patient died of pulmonary embolism; 78 were reviewed after a mean period of four years. Of these 78 patients 18 made a complete neurological recovery while 53 appeared to have benefited from the procedure; 25 remained unchanged. The best results were obtained in burst fractures at thoracolumbar and lumbar levels when a solitary detached fragment of a vertebral body had been displaced into the spinal canal. These results indicate that anterolateral decompression of the spinal canal should be considered, after careful evaluation, for certain injuries of the spine in which there is severe neural involvement.

Late-onset idiopathic scoliosis is associated with a rib hump in the thoracic region, and surgery is indicated when this deformity becomes unacceptable. Fifty patients with this deformity were treated by the Leeds procedure, which consists of segmental wiring to a kyphotically-contoured square-ended Harrington rod; this procedure not only derotates the spine but restores the natural thoracic kyphosis, thus avoiding subsequent buckling. All patients were followed up for a minimum of two years. Forty-two of these, who had a pre-operative Cobb angle of less than 60 degrees, were treated by one-stage instrumentation and fusion, while the remaining eight with greater curves underwent preliminary anterior multiple discectomy to provide flexibility with shortening. Postoperative loss of correction was not observed and there were no neurological complications.

The place and effectiveness of surgery for acromioclavicular dislocation is disputed. We have reviewed 29 patients all treated by an operation which holds the clavicle down to the coracoid process. This was effective in both acute and late cases, with rapid return to work, a low incidence of complications and no requirement for secondary procedures. We consider it to be the method of choice when operation is indicated.

The treatment of acromioclavicular injuries is controversial; few studies document the late results. We have reviewed 53 patients about five years after conservative management, in nine for subluxation and 44 for dislocation. Subjective and objective results were satisfactory in all cases except for one with painful subluxation, who was the only patient to change her occupation because of the injury. At review, joint stability was demonstrated by improvement in position and by the very small increase in the coracoclavicular gap on stress radiographs.

Forty-two shoulders in 37 patients with polyarthritis were treated with Neer total shoulder replacements and reviewed 12 to 66 months afterwards. There was good pain relief and improvement in function, but the range of movement was less than that seen after replacements for osteoarthritis; this may have been related to the fact that 34 shoulders had abnormal rotator cuff tendons. Although there was a high incidence of radiolucent lines around the glenoid component, there was no clinical evidence of loosening. There were a few complications, but on the whole we feel that the Neer total shoulder arthroplasty is a valuable procedure for a patient with polyarthritis.

The results of a prospective controlled trial of early mobilisation of Colles' fractures in the elderly are presented. Early mobilisation produced less pain and a stronger grip. It did not lead to any greater loss of reduction of the fracture. However, there was no significant improvement in the final range of movement of the wrist. Immobilisation of the wrist for six weeks in plaster is extremely inconvenient for the elderly living alone and the patients greatly appreciated the reduction of this period of time to a minimum.

We have reviewed 41 children under 15 years of age with a fracture of the radius and disruption of the inferior radio-ulnar joint. Despite the fact that the joint injury had not at first been recognised in 41% of cases and a variety of treatments had been used, the final results of conservative management were generally good. The more distal the radial fracture, the greater were the problems encountered.

The management of carpal dislocation after a late diagnosis is difficult. Open reduction is the usual treatment but collapse of the carpus may be hard to overcome without extensive dissection and consequent damage to the blood supply, ligaments and articular cartilage. A technique of distraction by an external fixator followed by semi-closed reduction is described and its successful use is reported in two cases.

Forty-eight consecutive patients (53 hips) were treated for moderate or severe slips of the upper femoral epiphysis between 1974 and 1984; 46 patients (96%) returned for clinical and radiological assessment at a mean of five years after operation. Twenty-three patients (23 hips) underwent a Dunn's open reduction and 25 patients (30 hips) were treated by epiphysiodesis and surgical osteoplasty as advocated by Heyman and Herndon. The results of the two methods of treatment are compared. Analysis revealed that 11 hips with moderate slip (30 degrees to 50 degrees) treated by the Heyman-Herndon procedure did significantly better than the 18 hips with severe slip (greater than 50 degrees) treated by the same method. Furthermore, when these hips with severe slip were compared to the hips treated by Dunn's open reduction, all of which were displaced greater than 50 degrees, the latter fared significantly better. The authors conclude that the Heyman-Herndon procedure gave consistently good results for moderate slips, but Dunn's open reduction gave better results for hips with severe slips.

A protocol for the treatment of fractures of the middle third of the femur by the early application of a hip spica has been evaluated in 191 children aged 10 years or less. Children without other injuries spent only a few days in hospital for the application and later removal of the spica. At all ages, anterior angulation of less than 20 degrees and valgus angulation of less than 15 degrees were accepted at the one-week review. Acceptance of shortening varied with the age of the child and the stage of treatment, but was 10% or less of the femoral length at the time of spica removal. At late review leg-length discrepancy was rare and clinically insignificant. This method of treatment was simple and effective. It dramatically reduced the cost of care and freed a number of children's hospital beds.

We have followed up a series of total hip arthroplasties performed for secondary osteoarthritis and analysed the results in relation to the osteoblastic response to the disease. This was assessed pre-operatively from the radiographic appearance, according to Bombelli's criteria (1983). Of 63 hips in 55 patients followed up for five to 13 years, 17 were hypertrophic, 24 normotrophic and 22 atrophic in type. The atrophic-type hips showed a high incidence of acetabular loosening, leading to unsatisfactory clinical results in 32%. By contrast, the hypertrophic-type hips had a low incidence of acetabular loosening, while the normotrophic type showed intermediate results. It was concluded that the osteoblastic response to osteoarthritis is closely related to acetabular loosening and to late clinical failure.

Total hip replacement for adults with unreduced congenital dislocation presents a difficult problem because soft-tissue contractures usually prevent sitting at the normal anatomical level. Extensive soft-tissue division or a high-level acetabulum leads to reduced function and poor fixation of the components. We describe a new technique for hip replacement in such cases. The shortened abductors and flexors are released proximally and excision of the upper third of the ilium allows them to be repaired without tension, while providing bone graft to reconstruct the acetabular roof. We report 12 such replacements in 10 patients with good results and few early complications.

The results of using the Ring uncemented polyethylene-to-metal (UPM) prosthesis in patients with protrusio acetabuli or dysplasia are reported. Fifty-four cases of protrusio were analysed and a modified method of measuring the deformity is described; after operation, remodelling of the medial wall had improved, on average, by 29.6%. For the dysplastic acetabulum the main difficulty is the lack of lateral support for the cup. In order to test the hypothesis that this support improves with an uncemented prosthesis, 38 hips with an average follow-up of 31 months were studied. Lateral support, measured radiographically, showed an average increase of 21%. The remodelling effect may be attributed to the biomechanical design of the prosthesis.

The purpose of this study was to establish if the Bateman prosthesis functions as a bipolar device moving primarily at the inner metal-on-polyethylene bearing as originally proposed, or as a unipolar hemiarthroplasty moving at the outer metal-on-cartilage surface as has recently been suggested. One hundred hips were examined at one year follow-up; 78 were examined again at two to four years. The replacement was performed for arthritis in 76 hips and for femoral neck fracture in 24. Movement was assessed both with and without weight-bearing. In 80% of the arthritis group the prosthesis functioned as a bipolar hip replacement with movement occurring primarily at the inner metal-on-polyethylene surface. By contrast, in 75% of the fracture group the prosthesis functioned largely as a unipolar device with movement occurring primarily at the outer metal-on-cartilage surface. In all cases examined serially the movement pattern was the same at two to four years as it has been at one year. Clearly, the action of the prosthesis depends on the condition of the acetabular cartilage.

In this study 201 elderly patients with femoral neck fractures were compared with 30 osteomalacic patients with the same injury. Hypocalcaemia and a raised alkaline phosphatase level are common biochemical abnormalities in elderly patients with femoral neck fractures. In only a minority of patients, however, were they associated with histologically proven osteomalacia. By using the combination of hypocalcaemia and a raised alkaline phosphatase it is possible to identify a subgroup (approximately 10% of all admissions) in whom osteomalacia is relatively likely.

We have reviewed 11 patients with idiopathic transient osteoporosis of the hip; the six who were women all developed the condition during pregnancy. Both simultaneous and sequential bilateral involvement were seen, but biochemical studies were consistently normal and one synovial biopsy showed only non-specific inflammation. Radioisotope bone scans and CT scans were useful to aid diagnosis. Treatment by limiting weight-bearing relieved symptoms, and spontaneous resolution was paralleled by radiographic remineralisation, usually within a few months. One patient developed a stress fracture of the hip and other areas of transient osteoporosis. A hip involved by the condition should be protected from overloading until bone density has recovered.

Sixty patients each of whom had a fracture of the lower limb a minimum of five years (median 11 years) previously were studied by photoplethysmography, foot volumetry, popliteal venous reflux and arterial Doppler measurements. The non-fractured limb was used as a control. Postphlebitic symptoms were present in 51% and signs in 49% of fractured limbs compared with 4% and 24% respectively in the control limbs. The incidence was greater in patients who had fractured 15 years or more previously than in those who had fractured 5 to 15 years previously. Eleven limbs had clinically disabling postphlebitic symptoms including venous ulceration. The postphlebitic syndrome following lower limb fractures in young patients is more common than generally appreciated and develops after a prolonged latent interval. A prospective randomised study using prophylactic anticoagulation for lower limb shaft fractures may be justified.

We have reviewed 60 patients with primary bone infections; 21 of these (35%) had subacute osteomyelitis, a figure which supports other recent observations that this variant of bone infection is becoming more widespread. In this group open culture and biopsy were necessary in order to exclude bony malignancy, and a raised erythrocyte sedimentation rate proved a useful diagnostic aid. All the patients with acute osteomyelitis or with vertebral infection responded to primary treatment, but five of those with subacute osteomyelitis had recurrences.

The role of antibiotics in the treatment of disc-space infection is controversial. This study assessed the tissue penetration of flucloxacillin and cephradine into the normal intervertebral disc after intravenous administration of a bolus dose of antibiotic. Twenty-five discs were removed from 12 adolescent patients having anterior spinal surgery to correct scoliosis; antibiotic had been administered between 30 minutes and four hours before operation. Despite high blood levels, no antibiotic could be detected by bioassay or by high-pressure liquid chromatography (h.p.l.c.) in any of the specimens from the nucleus pulposus or the annulus fibrosus.

A randomised prospective trial was undertaken of antibiotic prophylaxis given at various intervals before inflation of the tourniquet for arthroplasty of the knee. Cefuroxime assays of bone and subcutaneous fat from samples collected throughout the operation demonstrated that an interval of 10 minutes was necessary to obtain adequate prophylaxis. Improvement in the timing of antibiotic prophylaxis may result in a reduction in the incidence of infection.

The role of muscle function in the aetiology of recurrent dislocation of the patella has been examined. Eleven of the 12 patients we studied had joint hypermobility. Muscle biopsies from eight of nine patients treated by surgery had a predominance of abnormal Type 2C fibres, and three of six patients whose quadriceps muscles were studied by electromyography also had abnormal results. Our preliminary findings suggest that there may be a primary muscular defect in many cases of recurrent dislocation of the patella.

A retrospective review of 50 knees in 46 patients treated by arthroscopic removal of chondral flaps is reported. There was a relationship between the site of the flap and the type of symptoms; patellofemoral flaps produced anterior knee pain, posterior condylar flaps produced instability. At review after 18 to 36 months, after a second arthroscopy in eight cases, 44 of the 50 knees had retained significant improvement and 33 were symptom-free.

Thirty-six patients with reflex sympathetic dystrophy primarily affecting the knee were reviewed. Injuries or operation about the patellofemoral joint triggered its onset in 64% of patients. Co-existent mechanical derangement of the knee was present in 64% of patients. Those patients who underwent sympathetic blockade or sympathectomy within one year of onset of symptoms had significantly better pain and function scores than those in whom intervention was later. Early diagnosis remains the key to successful management. Surgery for co-existent mechanical derangement in the affected knee should not be performed until the syndrome is controlled.

Reflex sympathetic dystrophy of the knee has been studied in a series of 19 patients. Those diagnosed and treated early (at less than six months) did much better than those diagnosed and treated late. Nevertheless, when these patients were followed up at an average of 3.4 years from onset, not one was completely normal to objective tests with the Cybex II dynameter, an indication of the adverse prognosis with current methods of treatment.

A biomechanical study has been carried out on 20 cadaveric knees to investigate their load-absorbing mechanism. The impact load was applied using a weight falling onto the transected proximal femur and the force transmitted through the knee was measured at the transected distal tibia using a load transducer. The peak force transmitted increased as, sequentially, meniscus, articular cartilage and subchondral bone were damaged or removed. The most striking result was found in an implanted knee replacement where the transmitted force reached 180% of that in the intact knee. The results show that the joint has an impact-absorbing property in each segment and that in the osteoarthritic knee there is less absorption of shock than in the normal knee. The high impact force in an implanted knee suggests that microfractures of the cancellous bone might be expected and may produce loosening.

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.

We present the results of 38 children with leg inequality treated by circumferential periosteal release. Leg-length discrepancy was expressed as a percentage of the longer limb. All patients showed a decrease in percentage difference at one year after operation, the mean difference dropping from 7.24% to 5.45%. The size of the response was directly related to the age of the patient at operation, being more pronounced in the younger patients. The response was not related to sex, diagnosis, or rate of growth of the patient immediately preceding operation.

Comparisons were made between 54 children with resolving congenital talipes equinovarus deformity and 81 children whose feet required surgical correction. There was a significant difference in the incidence of bilateral deformity, sex ratio and family history of congenital talipes in the two groups. The children with resolving deformity had feet which were indistinguishable from the normal side of unilaterally affected children in their calf muscle measurements at six weeks of age, and in the range of movement and radiographs at four years of age. Those requiring surgery had varying degrees of muscle reduction, and although often well corrected, had a reduced range of movement and altered joint anatomy at four years of age. This suggests that they are two distinct populations.

A staged method of surgical management for congenital talipes equinovarus is described. The hindfoot was corrected and rebalanced early in 125 feet, and in 66 feet a second-stage medial forefoot correction was performed in the second, third or fourth year. The hindfoot relapsed in 19% and the forefoot in 9%; these feet were treated by further soft-tissue surgery. No bony operation was necessary. Assessment before and after operation allows comparison with other series.

Forty-four feet in 28 children previously treated by a one-stage posteromedial release operation (the Turco procedure) were reviewed clinically and radiologically to determine the cause of residual adduction of the forefoot. In 21 clinically adducted feet (48%) the main cause of residual deformity was metatarsus varus alone or metatarsus varus in spite of talonavicular overcorrection; in five feet the cause was talonavicular subluxation. There was no residual adduction in 23 feet (52%) but only 12 had normal radiographic measurements. In the remaining feet, various forms of spurious correction of metatarsus varus and talonavicular subluxation or both were seen, resulting in normal-looking feet. Recession of the origin of abductor hallucis and release of the short plantar muscles and fascia at the time of posteromedial release is recommended. The forefoot adduction was satisfactorily corrected in 91% of the feet subsequently operated on using this modified procedure.

Eight women had 10 toes treated for hallux rigidus by dorsal wedge osteotomy of the proximal phalanx and were reviewed after an average follow-up of 22 years. Five toes were symptom-free, four others did not restrict walking, and only one had required metatarsophalangeal fusion. We conclude that dorsal wedge osteotomy affords long-lasting benefits for hallux rigidus in the adolescent female.

A method of assessing foot movement suitable for use in clinical practice is presented. The method assesses the component of movement in the horizontal plane which is produced by rotating the calcaneum about the axis of the subtalar joint.

Ingrowing of the nail of the hallux has been ascribed to an abnormality of the shape of the nail; our prospective study was planned to test this association. Twenty-three consecutive patients and 23 age-matched controls were assessed by caliper measurement and standard photographs, before a first operation for ingrowing toenail. We found no differences in shape between the toenails of the patients and those of the controls, both groups showing great variation. Our results suggest that the ingrowth is not commonly associated with an abnormal shape of the nail.