An unusual form of chronic osteomyelitis in children is described. Three children presented with clinical signs of acute infection and radiographs revealed a pre-existing destructive bone lesion. Exploration of the lesions did not release pus, and cultures for pathogens were negative. The lesions healed but the symptoms returned intermittently over many years with the development of sclerosis and disturbance of bone growth. The lesions did not respond to antibiotics or operative treatment. All the patients were fully investigated and although the erythrocyte sedimentation rate was increased the white blood count was seldom abnormal. There were no neurological abnormalities. Two of the three cases required an osteotomy to correct malalignment. A comparison is made between the findings in these three patients with similar cases reported recently and possible causes are discussed.

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.

In spina bifida the femoral neck can develop either the well-known coxa valga or the hitherto unreported coxa vara. Twenty-three cases of coxa vara in spina bifida are reported. These result from spontaneous separation of the upper femoral epiphysis (10 cases), spontaneous fracture of the femoral neck (three cases) and iatrogenic avascular necrosis of the upper femoral epiphysis (10 cases).

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.

A study of cadaveric vertebral biopsy and a review of 100 clinical biopsies has shown that needles and trephines producing tissue specimens of two millimetres or more in diameter can be expected to give a high degree of diagnostic accuracy. The erythrocyte sedimentation rate was a more useful screening investigation than were estimations of serum alkaline phosphatase. The complications are described. It is suggested that patients with painful thoracic metastases and evidence of progressive cord compression should have early decompression after open biopsy if further neurological compromise is to be prevented.

This paper reports a prospective study of the value of ultrasonography in detecting lesions of the lumbar spine in patients with compressive sciatica. The measurements of the diameter of the spinal canal obtained by using ultrasound were compared with the findings at operation in 17 patients in whom a total of 50 sites were examined. The ultrasound beam failed to penetrate the spinal canal at 15 sites and at only 10 of the remaining 35 sites did the ultrasound correctly detect narrowing. It is concluded that ultrasonography is unreliable in identifying the site of compression of the spinal cord and nerve roots. The technical limitations and the probable causes of failure of the technique are discussed.

Fracture separation of the capital femoral epiphysis occurring during attempted closed reduction of a traumatic dislocation of the hip is described in two adolescents. Although this complication is extremely rare, the prognosis of fracture separation with dislocation of the epiphysis is known to be poor. Avascular necrosis subsequently developed in both cases. The importance of gentle manipulative reduction under general anaesthesia with complete muscle relaxation is emphasised.

The long-term results of 74 cases of simple traumatic dislocation of the hip are reported and the effects of the cause of dislocation and of the occupation and age of the patient on the prognosis are assessed. The average follow-up was 14.65 years. Contrary to the widely held view that there are no long-term complications of this injury, we found that, overall, 24 per cent of the dislocated hips went on to develop osteoarthritis. The incidence was highest in manual workers with 37.5 per cent of miners injured in car accidents developing osteoarthritis compared with only 20 per cent of the sedentary workers. The incidence of osteoarthritis in miners injured in pit accidents was 45 per cent compared with only 17 per cent for those involved in motor cycle accidents. These differences could be due to continued heavy work after the accident rather than to any difference in the violence of the initial injury. The incidence of osteoarthritis was highest in patients aged between 31 and 40 years and, as expected, was found to increase with length of follow-up.

Modern anthropometric techniques were used to investigate two groups of subjects, one with various syndromes associated with pain in the lower back and the other a control group. Analysis confirmed previous reports that people prone to pain in the back have a greater standing height than people who are not. To investigate this further two new components of height, namely pelvic height and suprapelvic height, were calculated in addition to the established calculation of subischial height. Consecutive components, namely suprapelvic height, pelvic height and subischial height, together constituted the standing height of a subject. The main finding of this investigation was that the relatively large standing height of the subject prone to back pain was due only to the pelvic component.

Three amputated legs with tibial dysplasia were studied by radiography, arteriography and anatomical dissection. The radiographic appearances were the same as the Type 1b tibial dysplasia described by Jones, Barnes and Lloyd-Roberts (1978) in that the tibiae were absent but the lower femoral epiphyses were normal. However, our anatomical findings differed from those of Jones et al. since no bony or cartilaginous anlage of the proximal tibia was found in any of the three legs. The pattern of vascular anomaly was identical in the three legs and similar to the findings of Hootnick et al. (1980) in congenital short fibula. Congenital fusion of the subtalar joint was a constant finding. These results support the hypothesis that the arterial and skeletal systems are vulnerable to a teratogenic insult in the fifth week of embryonic life. The bony and arterial anomalies should be borne in mind by the surgeon attempting reconstructive surgery for this condition.

Three cases of a rare complication of Salter Type II fracture-separations of the distal tibial epiphysis are described. Interposition of the anterior tibial neurovascular bundle between the displaced epiphysis and the lower tibia prevented reduction and, in two patients, the blood supply to the foot was compromised. Open reduction and internal fixation resulted in a satisfactory outcome in each case.

The results of total knee replacement in five patients aged between 22 and 37 with severe haemophilia A or B are described. All patients had been managed conservatively without success. Frequent bleeds, severe pain and limitation of movement were the indications for operation. Despite close haematological surveillance, bleeding problems occurred in three of the patients and large quantities of plasma concentrates were required. Review of the patients over a period of 25 to 48 months after operation showed dramatic lessening of pain and maintenance of a satisfactory range of movement. The frequency of haemarthrosis diminished markedly and the requirements for factor concentrate in the years after operation fell substantially. Two patients returned to employment. Total knee replacement led to marked clinical improvement in all the patients, but the long-term results are not yet known.

The development of lateral tibial torsion in the paralysed lower limb is well documented, but its pathogenesis is poorly understood. This paper attempts to provide an explanation for its development when it is associated with a varus or equinovarus deformity of the hindfoot. Correction of the lateral tibial torsion by supramalleolar derotation tibial osteotomy and reorientation of the ankle mortise appear to unlock the talus from the laterally rotated position, correcting a mobile hindfoot varus deformity and altering soft-tissue tensions about the ankle so that the correction achieved is maintained. In the presence of a fixed hindfoot deformity, supramalleolar derotation tibial osteotomy is useful as a first-stage procedure before corrective osteotomies of the foot. The operation described is technically simple and carries a low morbidity. Twenty supramalleolar derotation tibial osteotomies in 18 patients have been performed with satisfactory results and few complications.

The results of 63 operative repairs of chronic tears of the rotator cuff in 61 patients are reviewed retrospectively; the mean follow-up was 32.7 months. Fifty-four patients presented with symptoms of persistent pain and seven patients with gross loss of movement. All the patients had failed to respond to conservative treatment. Results were assessed in terms of relief of pain, restoration of movement, the patients' ability to return to work and whether they were satisfied with the results. Overall, a good result in terms of relief of pain was achieved in 40 shoulders. In 31 shoulders (30 with pain and one without pain) the operation included particular measures to decompress the subacromial space; 26 of the patients achieved relief of pain which was significantly better than in those patients whose operation did not include a decompression. The complications and failures are discussed. It is suggested that operative repair of the chronically torn rotator cuff of the shoulder is a worthwhile operation and that the operation should include an adequate decompression of the subacromial space.

Degenerative changes of the first carpometacarpal joint commonly cause pain, weakness and adduction deformity. Many patients respond to conservative treatment, but in resistant cases an abduction wedge osteotomy of the base of the first metacarpal has been found to relieve symptoms with less complications than other operations. Twenty-one patients with 23 osteotomies have been reviewed, with a follow-up from 2 to 17 years. All have had lasting relief from pain and consider that they have full function, with no stiffness or limited abduction. Osteotomy is indicated mainly for cases where the arthritis is confined to the carpometacarpal joint, but also relieves pain in cases of peritrapezial arthritis.

We report for the first time the combination of congenital sacral agenesis and congenital absence of the pituitary gland. This rare association is described in a baby born to a diabetic mother. The baby died at the age of 11 weeks after a cardiorespiratory collapse. The findings at necropsy, which included unusual neurological and visceral anomalies, are reported. We draw attention to the increasing evidence that maternal diabetes is a factor in producing foetal malformations.

Paraplegia occurred in an adolescent girl with osteogenesis imperfecta after chiropractic manipulation. The child had been able to walk freely out of doors. Complete motor paralysis with sensory sparing resulted due to anterior compression of the cord by spondyloptotic cervical vertebrae. Reconstructed computerised tomography was very helpful in demonstrating the abnormality. Anterior and then posterior decompression relieved the tethered spinal cord and were supplemented with bone grafting. Early diagnosis and surgical treatment will prevent similar neurological accidents.

The aim of this study was to try to elucidate the increased susceptibility of the neck of femur to fracture. Quantitative polarised light microscopy has been applied to fresh, undecalcified sections of samples of bone taken from the site of fracture, in specimens taken at operation from patients with fractures of the femoral neck or osteoarthritic femoral heads or from the equivalent site from otherwise normal subjects at necropsy. In all 21 specimens of fractured necks of femur, but in none of the other specimens, relatively large crystals (up to 2.5 X 0.5 micrometres) were found close to the site of fracture; the properties of these crystals were compatible with their being apatite. Measurement of the natural birefringence of the collagen showed no difference in the orientation of the collagen in all three types of specimen. However, the orientation of acidic glycosaminoglycans, measured by the birefringence of alcian blue bound to these moieties, was 45 per cent lower in the specimens from fractured necks of femur than in the other specimens, even though the total content of acidic glycosaminoglycans was unchanged. Although the decreased orientation was most marked close to the site of fracture, it was still apparent 15 millimetres from that site. These changes were unlikely to be simply the sequelae of fracture since they were not found in traumatic fractures of other bones. Thus it is conceivable that changes in the orientation of the ground substance allow formation of relatively large crystals of apatite and that such crystals, in the microcrystalline mass of apatite, are the cause of the increased fragility of such bones.

Radiographs of the foot and hip in 61 patients with fractures of the upper end of femur have been studied, noting the progressive loss of bone trabeculae with age. The trabecular pattern in the calcaneum (expressed as the calcaneal index) closely parallels that in the upper end of the femur (Singh's index) and is easier to assess. Both indices have a significant correlation with age.

Forty-one cadaveric lumbar intervertebral joints from 18 spines were flexed and fatigue loaded to simulate a vigorous day's activity. The joints were then bisected and the discs examined. Twenty-three out of 41 of the discs showed distortions in the lamellae of the annulus fibrosus and, in a few of these, complete radial fissures were found in the posterior annulus.

The significance of the posterior cruciate ligament in the stability of the knee was investigated in dogs and it was compared with that of the anterior cruciate ligament by studying the changes produced in the knee after transection of either ligament. Osteophyte formation and changes in articular cartilage were less prominent after division of the posterior cruciate ligament. A complete longitudinal tear of the medial meniscus was found in eight out of the 10 dogs who had undergone section of the anterior cruciate but in none of the 10 with section of the posterior cruciate. It appears that, in dogs at least, the posterior cruciate ligament is less important than the anterior in the stability of the knee.

The scalpel blades used during 187 operations were cultured. At each procedure the knife used to incise the skin was discarded immediately and a fresh knife was used to complete the operation. The results showed that there was no difference in the bacterial growth between the two knives. From these results it would appear that the practice of changing blades after incising the skin is an unnecessary precaution in the prevention of bacterial contamination of clean wounds.