We performed superselective angiography in 28 hips in 25 patients with Perthes’ disease in order to study the blood supply of the lateral epiphyseal arteries (LEAs). Interruption of the LEAs at their origin was observed in 19 hips (68%). Revascularisation in the form of numerous small arteries was seen in ten out of 11 hips in the initial stage of Perthes’ disease, in seven of eight in the fragmentation stage and in five of nine in the healing stage. Penetration of mature arteries into the depths of the epiphysis was seen in four of nine hips in the healing stage. Vascular penetration was absent in the weight-bearing portion of the femoral head below the acetabular roof. Interruption of the posterior column artery was seen where it passed through the capsule in seven hips when they lay either in internal rotation or in abduction with internal rotation. We suggest that in Perthes’ disease the blood supply of the LEAs is impaired at their origin and that revascularisation occurs from this site by ingrowth of small vessels into the femoral epiphysis. This process may be the result of recurrent ischaemic episodes

Of 54 patients with posterior dislocations of the hip of type I and type II (Stewart and Milford 1954), 47 were followed for a mean period of 6.7 years (2 to 11). Of these, 23 had dislocation with minimal lesions of the acetabulum (type I) and 24 had an avulsed dorsocranial fragment (type II). All were reduced by closed methods within six hours. The subsequent treatment of type I dislocations was conservative. At the beginning of the period type II injuries were treated conservatively, but surgery was increasingly chosen for later cases. Type I dislocations had significantly better results (p < 0.05) than type II fracture-dislocations, regardless of the method of treatment. There were no essential differences between the results of surgical and conservative treatment in type II dislocations

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

We investigated the fixation of fully-threaded cementless acetabular prostheses in 20 patients with osteoarthritis, measuring the migration of the cup using roentgen stereophotogrammetric analysis (RSA). All the cups migrated proximally, 13 moved laterally or medially, and nine moved anteriorly or posteriorly in the first two postoperative years, the average migration being 1.1 to 1.4 mm in either direction. Rotatory movements of up to 5.7 degrees were found in nine of the 13 hips where this analysis could be performed. Movements of cobalt-chrome (12) and titanium alloy (8) cups did not differ significantly. Seventeen of the 20 patients had some pain two years after the operation. The migration of the prostheses indicates that 'osseointegration' had not occurred. The combination of this with persistent pain suggests that the long-term results will be unfavourable

We present a study of 30 fusion operations in 26 rheumatoid arthritics with cervical spine instability. Atlanto-axial instability was present in 15, of whom 12 were fused; three had cord involvement and all made a partial or complete recovery following fusion. Cranial settling necessitated cranio-cervical fusion in four patients; all fused, and one with myelopathy was relieved. Subaxial instability required fusion in seven cases; two postoperative deaths followed the only two anterior interbody fusions. Posterior fusion was successful in the other five, with remission of neurological compromise in the three with myelopathy and one with radiculopathy. We conclude that neurological compromise in an unstable but mobile rheumatoid cervical spine can usually be brought to remission by immobilisation alone, so decompressive procedures are unnecessary in the first instance

We have analysed the initial displacement and the retention of position after reduction of 192 spiral fractures of the tibial shaft. In fractures with an initial lateral displacement of one half the width of the shaft or more, successful retention of position after the primary closed reduction was achieved in only 18%. The direction of displacement between the tibial fragments showed little variation; the proximal fragment was always medial and anterior to the distal. This resulted in an increased space between the proximal tibial fragment and the shaft of the fibula in the plane of the interosseous membrane. There was a strong correlation between the initial displacement and the initial shortening. No evidence of a posterior soft-tissue hinge, able to facilitate closed reduction, could be found. Consequently, in treating severely displaced spiral fractures, open reduction and internal fixation or a few weeks' initial calcaneal traction seem to be the rational alternatives

The accessory navicular is occasionally the source of pain and local tenderness over the instep. If conservative measures fail, surgical treatment may be required and the results of 62 operations to one or both feet in 47 patients are reported. Twenty-six patients were treated by the Kidner operation, in which the main insertion of the tibialis posterior is re-routed; in the remaining 21 the ossicle was merely excised. Excision was as effective as the Kidner technique, provided that the medial surface of the main navicular bone was contoured to prevent any residual prominence. Both procedures were successful in relieving symptoms in the majority of cases and failures resulted from errors in the selection of patients or in the surgical technique. Correction of any associated flat foot was secondary to growth and maturation of the foot rather than to the operation; hence the Kidner procedure does not confer any particular advantages over simple excision

A clinical, cadaveric, biomechanical and radiological investigation of the pathogenesis of idiopathic scoliosis indicates that biplanar asymmetry is the essential lesion. Many normal children have coronal plane asymmetry (an inconsequential lateral curvature of the spine), and certainly all have vertebral body asymmetry in the transverse plane, but when median plane asymmetry (flattening or more usually reversal of the normal thoracic kyphosis at the apex of the scoliosis) is superimposed during growth, a progressive idiopathic scoliosis occurs. Idiopathic kyphoscoliosis cannot and does not exist, from the mildest cases in the community to the most severe cases in pathology museums. Median plane asymmetry is crucial for progression and the lateral profile of the spine must be carefully scrutinised. Increased anterior vertebral height at the apex of the curve with posterior end-plate irregularity characterises the median plane asymmetry and suggests that idiopathic scoliosis is the reverse of Scheuermann's disease

Dislocations of the cervicothoracic junction are frequently missed. Experience of this rare injury over 27 years at the Spinal Injuries Unit in Sheffield confirms that nearly two-thirds were not properly diagnosed on admission. Only two of the 14 dislocations studied were reduced by conservative methods and these were both associated with fractures of the posterior bony elements. Open reduction is necessary to replace pure dislocations at the C7-T1 level. It seems likely that the spinal cord lesion is not influenced by reduction of the displacement. The three patients who had an incomplete lesion of the spinal cord made excellent neurological recoveries although none of the dislocations was reduced. It is concluded that on theoretical grounds it is justified to embark on operative reduction of displacements at this spinal level only if the cord lesion is incomplete, nerve root recovery therefore possible, and if the operation can be brought about soon after the injury

An electrophysiological system for monitoring the spinal cord during operations for scoliosis is described. During the development of the technique the recording of cortical somatosensory evoked potentials from the scalp and spinal somatosensory evoked potentials from the laminae or spines was superseded by the positioning of recording electrodes in the epidural space cephalad to the area to be fused. All recordings were made in response to stimulation of the posterior tibial nerve at the knee. Results in 138 patients are presented and the findings in three patients who exhibited neurological deficits after operation are described. It is concluded that spinal somatosensory evoked potentials are sensitive to minor spinal cord impairment, possible due to ischaemia, and that these changes may be reversed when the cause is quickly remedied. The monitoring system interferes minimally with anaesthetic and surgical procedures and is now performed as a routine

Seventy-eight patients who had been operated on for bony entrapment of lumbar nerve roots were studied in an attempt to define the clinical syndrome, and to assess the results of a new technique of decompression which preserves spinal stability. The mean age of the patients was 45 years and 28 of them had previously undergone spinal operations. Pain in the leg was the predominant symptom, with evidence of motor involvement in half of the patients. Signs of nerve root tension were found in only one-third of the patients. The principal factor in the aetiology was degenerative change in the posterior facet joints. Decompression was achieved by a partial undercutting facetectomy. Fifty-nine per cent of the patients obtained a "good" result and 85 per cent were satisfied with the result of their operation. Successful partial facetectomy for bony entrapment of lumbar nerve roots produced rapid and lasting relief of pain

The different methods described in the literature for the reduction of severe spondylolisthesis are reviewed. The case histories of two girls with neurological deficits in their legs due to Grade IV spondylolisthesis are described. Reduction and fusion by the posterior route in a one-stage operation were performed on these patients. For this purpose special instruments have been designed to exert a controlled force on the displaced vertebra in two perpendicular directions. Technical details of the procedure are reported. In both patients intervertebral and posterolateral fusion were carried out. Fusion was successful and redisplacement did not occur. There have been only few descriptions in the literature of a technique that reduces and stabilises spondylolisthesis in one stage. However, only patients with Grade III and IV spondylolisthesis require reduction and in less severe cases fusion without reduction is sufficient

Thirty-three children with traumatic dislocation of the hip who had been treated at the Hospital for Sick Children between 1960 and 1977 were reviewed. The amount of trauma causing dislocation of the hip in younger children was less than that for older children. The most frequent complication was soft-tissue interposition which usually required a posterior arthrotomy to clear the interposed tissue. Less frequent complications included avascular necrosis, redislocation of the hip and an irreducible hip. Nineteen children were reviewed with an average follow-up time of 10 years. Clinical examination indicated that 84 per cent of these hips were normal but the radiographs showed that 47 per cent of the dislocated hips had a coxa magna of two millimetres or more. There was no correlation between the development of coxa magna and the clinical result

The management of twenty-one children with a defect of the tibial shaft due to acute haematogenous osteomyelitis is described. Half the defects were due to removal of the sequestrum before the involucrum had formed. Only four patients, all under ten years of age, had spontaneous regeneration of the shaft. Eleven children had a posterior tibiofibular graft and six had a transfer of the ipsilateral fibular diaphysis. The results of operation were superior to those of spontaneous regeneration. All the grafts united and the children returned home to lead normal lives. Shortening was only a problem when growth plates or adjacent joints had been damaged. We now leave the sequestrum for up to one year after the onset of infection. If the involucrum fails to form we reconstruct the tibia as soon as possible after sequestrectomy

Ninety-seven patients suffering from painful arc syndrome of the shoulder were studied. Local anaesthetic and radiographic contrast investigations were carried out. One-third of the patients had lesions in the posterior part of the rotator cuff which resolved after injections of local anaesthetic and steroid. One-third had anterior lesions in the subscapularis tendon: almost all resolved under the same regime but two required division of the coraco-acromial ligament. The remaining third had lesions of the supraspinatus tendon, usually associated with degeneration of the acromio-clavicular joint: most of these failed to gain relief from the local anaesthetic and steroid. Twenty-two operations were performed either by a transcromial or by a deltoid splitting approach. Excision of the outer end of the clavicle and division of the coraco-acromial ligament abolished the pain in most cases

The costo-clavicular ligament is always ruptured in dislocation at the sterno-clavicular joint. Anterior, superior or posterior displacement of the medial end of the clavicle may occur. Acute dislocation usually responds to conservative treatment and operation is seldom required. Chronic, or recurrent, dislocation may cause pain and disability on strenuous activity and necessitate surgical treatment. The operation of tenodesis of the subclavius tendon with capsulorrhaphy described by Burrows (1951) has been adopted. The intraarticular meniscus is often damaged and displaced, and may block reduction; its removal is then necessary. In addition, a threaded Steinmann pin transfixing the joint has been found useful to maintain the stability of reduction. The operation has been performed on five patients, four of whom had excellent results. The fifth patient disrupted the repair in a drinking bout shortly after the operation

1. A sagittal technique for below-knee amputation for ischaemic gangrene based on mediolateral musculo-cutaneous flaps is described, similar to the one independently presented by Tracy (1966). 2. The results with this method are illustrated by the evolution of the below-knee healing rate over six years in 172 patients with ischaemic gangrene. 3. A comparison between sagittal and conventional flap techniques shows a reamputation rate of six out of fifty-eight in the former and sixteen out of forty-one in the latter. 4. The overall relative knee joint preservation during 1971 was 82 per cent, and the frequency of attempted below-knee amputation was 93 per cent. 5. It is concluded that the sagittal technique has several advantages in comparison to the posterior flap technique, and that the potential for healing is on the same high level. 6. A fully controlled comparison between different techniques is proposed

1. Anterior transperitoneal lumbar fusion is a successful method of stabilising painful mechanical derangements which have not responded to the usual conservative measures. 2. The operation in this series was done mainly for backache; it should not be contemplated if there is definite evidence of nerve root compression, because sequestrated disc material cannot be removed from the spinal canal from the anterior route. 3. Careful technique has resulted in few complications attributable to the operation. 4. This method is sometimes thought to be inapplicable in cases of spondylolisthesis with a displacement of more than one-third. However, in this series we have seen the block type of graft used with a good measure of clinical and radiological success. 5. There is no doubt that for those patients who have had previous unsuccessful laminectomies or posterior fusions anterior interbody fusion offers an excellent prospect of recovery

We used fluoroscopy to study the kinematics of the knee in 47 patients with total knee arthroplasty (TKA) and four control subjects with normal knees while performing a single-leg deep-knee bend. The videos were analysed using still photographs taken at 5 degrees increments of flexion. Femorotibial contact points, patellar ligament rotation, and patellar rotation were calculated from each image. Maximum weight-bearing flexion was determined for each knee. Compared with the control group, posterior-cruciate-retaining TKA did not reproduce normal knee kinematics in any case, but showed a starting point posterior to the tibial midline which translated anteriorly with flexion. The curves from successive knee bends could not be consistently reproduced. Under weight-bearing conditions, the maximum flexion for any PCR TKA was 98 degrees and several patients could not flex beyond 70 degrees

Visualisation of periacetabular osteolysis by standard anteroposterior (AP) radiographs underestimates the extent of bone loss around a metal-backed acetabular component. We have assessed the effectiveness of standard radiological views in depicting periacetabular osteolysis, and recommend additional projections which make these lesions more visible. This was accomplished using a computerised simulation of radiological views and a radiological analysis of simulated defects placed at regular intervals around the perimeter of a cadaver acetabulum. The AP view alone showed only 38% of the defects over all of the surface of the cup and failed to depict a 3 mm lesion over 83% of the cup. When combined with the AP view, additional 45° obturator-oblique and iliac-oblique projections increased the depiction, showing 81% of the defects. The addition of the 60° obturator-oblique view further improved the visualisation of posterior defects, increasing the rate of detection to 94%. Based on this analysis, we recommend using at least three radiographic views when assessing the presence and extent of acetabular osteolysis