Two hundred and fifty cases of myelodysplasia were reviewed in relation to spinal deformity. Approximately half of the children had, or were expected to develop, curves severe enough to need operations and only 10 per cent maintained completely undeformed spines. The most frequent deformity was scoliosis which could be subdivided into congenital and developmental types. The latter was of mixed aetiology, neuromuscular imbalance and asymmetry of the neural arch both contributing, while in some cases no causative factors could be identified. The best early indicator that developmental scoliosis was likely to appear was a high segmental level of both the neurological deficit and the neural arch defect. Deformity was very unlikely to start after the age of nine years.

1. Eighty-nine cases of Perthes' disease are reviewed.

2. The prognosis varies with the amount of the epiphysis involved.

3. It is possible to assess the amount of epiphysial involvement by a study of the early radiographs. Cases were allocated to four groups on this basis.

4. It is confirmed that both sex and age at the time of diagnosis influence the final prognosis. The reasons for this are discussed.

5. The concept of "the head at risk" is suggested and radiological signs described to diagnose such cases.

6. It is hoped that the classification suggested may in future act as a basis for comparisons of treatment.

1. The clinical features in twenty cases of osteoid osteoma have been analysed and compared with other cases reported in the literature.

2. The lesion is regarded as a benign neoplasm and its unusual clinical behaviour is attributed to its vascular nature.

3. The frequency with which an erroneous diagnosis of "neurosis" is made is stressed.

We investigated fixed flexion deformity (FFD) after total knee replacement (TKR). Data relating to 369 cruciate-retaining unilateral TKRs performed at a single institution were collected prospectively. Fixed flexion was measured pre-operatively and at one week, six months, 18 months, three years and five years after surgery.

Using binary logistic regression, pre-operative FFD was a predictor of post-operative FFD > 10° at one week (p = 0.006) and six months (p = 0.003) following surgery. Gender was a predictor at one week (p = 0.0073) with 24% of women showing a FFD > 10° compared with 37% of men.

We have shown that a gradual improvement in knee extension can be expected up to three years after surgery in knees with FFD. By this time residual FFD is mild or absent in the majority of patients, including those who had a severe pre-operative FFD.

The progression of post-tubercular kyphosis in 61 children who received ambulatory chemotherapy was studied prospectively. The angles of deformity and kyphosis were measured for each patient at diagnosis, 3, 6, 9, 12 and 18 months later and every year thereafter for 15 years. During the course of the disease signs of instability appeared on the radiographs of some of the children. These were dislocation of the facets, posterior retropulsion of the diseased fragments, lateral translation of the vertebrae in the anteroposterior view and toppling of the superior vertebra. Each sign was allocated one point to create a spinal instability score. The influence on the progression of the deformity of the level of the lesion, the vertebral body loss, the number of segments involved, the angle of deformity before treatment and the spinal instability score was analysed.

The mean angle of deformity at the start of treatment was 35°. This increased to 41° at 15 years. Progression occurred during the active phase of the disease and again after cure when variations in progression were observed. Type-I progression showed an increase in deformity until growth had ceased. This could occur either continuously (type Ia) or after a lag period of three to five years (type Ib). Type-II progression showed decrease in deformity with growth. This could occur immediately after the active phase (type IIa) or after a lag period of three to five years (type IIb). Type-III progression showed minimal change during either the active or healed phases and was seen only in those with limited disease.

Multiple regression analysis showed that a spinal instability score of more than 2 was a reliable predictor of patients with an increase of more than 30° in deformity and a final deformity of over 60°. Since signs of radiological instability appear early in the disease, they can be reliably used to identify children whose spine is at risk for late progressive collapse. Surgery is advised in these cases.

We performed a retrospective review of 27 scoliotic patients with syringomyelia using MRI. Their mean age at the first MRI examination was 10.9 years, and at the final review 15.8 years. The mean ratio of the diameter of the syrinx to the cord on the midsagittal MRI (S/C ratio) decreased from 0.49 to 0.24; 14 patients showed a decrease of 50% or more (reduction group). In this reduction group, the cerebellar tonsillar herniation decreased from a mean of 11.3 mm to 6.0 mm, and some improvement in dissociated sensory disturbance was seen in nine of 13 patients. The scoliosis improved by 5° or more in six patients in the reduction group. Our results indicate that spontaneous shrinkage of syringomyelia in children is not unusual and is associated with improvement in the tonsillar herniation, the scoliosis and the neurological deficit.

We studied 1061 children with myelomeningocele, reviewing 3184 pelvic radiographs from 802 patients. Hip dislocation had occurred by the age of 11 years in 28% of children with a thoracic neurosegmental level, 30% of those with an L1/2 level, 36% of L3, 22% of L4, 7% of L5 and only 1% of those with sacral levels. Hip dislocation was not inevitable even when there was maximal muscle imbalance about the hip. The average hip flexion contracture in children aged 9 to 11 years was significantly greater in those with thoracic (22 degrees) and L1/2 (33 degrees) levels than in those with L4 (9 degrees), L5 (5 degrees) or sacral (4 degrees) levels. Our findings indicate that muscle imbalance is not a significant factor in the production of flexion deformity or dislocation of the hip; both are commonly seen in the absence of imbalance. The restoration of muscle balance should no longer be considered to be the principal aim of the management of the hip in children with myelomeningocele.

We studied the prognostic value of MRI in 32 radiographically normal, asymptomatic hips in 25 patients at risk of osteonecrosis from glucocorticoids or alcoholism. The early findings were band-like hypointense zones on spin-echo images. No operations were performed. Life-table survival curves showed that femoral heads in which the hypointense zone traversed the middle portion of the head were most at risk of subsequent segmental collapse.

Anterior knee pain in adolescents is generally recognised as a common but benign self-limiting condition. Although many operative procedures for its treatment have been proposed, there is little statistical evidence that they are more effective than expectant management. A group of 54 adolescent girls has been followed for two to eight years from presentation with anterior knee pain. Although some pain persisted in the majority, in many the symptoms declined in severity. This study provides a baseline for comparison with the results of operative intervention; it is suggested that surgical treatment is unproven and unnecessary.

Fifty-four adults with eighty hips affected by congenital disease which had not been treated have been reviewed. Fifty-nine per cent of forty-two dislocated hips had fair or poor grading scores. The incidence of osteoarthritis was markedly increased in the presence of a well-developed false acetabulum. Unilateral dislocation led to valgus deformity and degenerative changes in the ipsilateral knee in seven of twenty-two patients. Dislocation did not increase the incidence of symptomatic lumbar spondylosis. The height of the dislocated head on the ilium was not found to be related to the prognosis for the hip, the knee or the lumbar spine and did not correlate with the development of the false acetabulum. Frank congenital subluxation eventually led to osteoarthritis of the hip.

1. One hundred and twenty-six metacarpo-phalangeal joints affected by rheumatoid arthritis were studied macroscopically at either synovectomy or arthroplasty.

2. The sites and extent of the initial erosion corresponded with the sites and size of the synovial pouches.

3. The areas of cartilage degeneration were related to the degree of flexion, ulnar deviation and subluxation of the proximal phalanx on the metacarpal head.

4. The routine radiographic findings were not a true reflection of all the pathological changes within the joint.

5. It is suggested that by encouraging joint movement and preventing deformity the degree of cartilage degeneration may be diminished.

Experience in the management of fourteen children with melorheostosis has been reviewed. The principal and presenting clinical features were unilateral soft-tissue contractures associated with inequality of limb length. In contrast to the disease in adults, pain occurred infrequently and was never intense. The average interval between the discovery of the clinical features and the correct diagnosis was six years. The distinctive radiographic feature in the child was an endosteal pattern of hyperostosis marked by streakiness of the long bones and spotting of the small. This differs from the usual subperiosteal or extracortical pattern of hyperostosis seen in adults. The surgical treatment of the contractures proved difficult and recurrence of the deformity was the rule. Distal ischaemia occurred when the chronically contracted and flexed joint was rapidly extended.

1. Details are given of sixty-three consecutive cases with a history of pleural effusion seen at an orthopaedic hospital.

2. Twenty-four of these were post-primary effusions occurring before the onset of symptoms of the orthopaedic lesion. The bone and joint lesions ultimately developing in this group of patients were widely scattered throughout the skeleton.

3. Three others were secondary to adult-type pulmonary lesions.

4. Thirty-six patients had a pleural effusion after the beginning of their orthopaedic tuberculous history. Seven were certainly secondary to operative intervention, six in the thorax near the parietal pleura (costotransversectomy or antero-lateral decompression of the cord) and one from a haematogenous dissemination after fusion of a hip joint.

5. The remainder of this group with pleural effusion during the history of their orthopaedic tuberculous disease numbered twenty-nine. Of these, twenty-five suffered from disease of the thoracic spine; in two more details are defective. Only two definitely had neither pulmonary nor thoracic spinal disease; their lesions were in the lumbar spine.

The conclusion is drawn that the overwhelmingly common cause of pleural effusion in patients with orthopaedic tuberculosis who have normal lungs and have not recently suffered spinal decompression is transpleural infection from thoracic spinal disease and that the sequence is by no means rare. It had occurred in approximately one in six of 145 patients with thoracic Pott's disease seen during this investigation.

6. Details are given of a group of cases with thoracic paravertebral abscess tracking laterally. When the abscess is well clear of the spine and spinal ligaments it may project forwards and radiologically it may appear in the antero-posterior chest film as a shadow in the middle of one or other lung field rather than as a shadow obviously connected with the central paravertebral abscess. Aspiration will yield pus from this posterior extra-pleural abscess extension.

7. The belief that Pott's disease most commonly follows direct spread from caseous paraaortic glands secondary to tuberculous pleurisy is discussed. It is concluded that the evidence is insufficient for so sweeping a statement.

We retrospectively examined the prevalence and natural history of asymptomatic lumbar canal stenosis in patients treated surgically for cervical compressive myelopathy in order to assess the influence of latent lumbar canal stenosis on the recovery after surgery. Of 214 patients who had undergone cervical laminoplasty for cervical myelopathy, we identified 69 (32%) with myelographically documented lumbar canal stenosis. Of these, 28 (13%) patients with symptomatic lumbar canal stenosis underwent simultaneous cervical and lumbar decompression. Of the remaining 41 (19%) patients with asymptomatic lumbar canal stenosis who underwent only cervical surgery, 39 were followed up for ≥ 1 year (mean 4.9 years (1 to 12)) and were included in the analysis (study group). Patients without myelographic evidence of lumbar canal stenosis, who had been followed up for ≥ 1 year after the cervical surgery, served as controls (135 patients; mean follow-up period 6.5 years (1 to 17)). Among the 39 patients with asymptomatic lumbar canal stenosis, seven had lumbar-related leg symptoms after the cervical surgery.

Kaplan–Meier analysis showed that 89.6% (95% confidence interval (CI) 75.3 to 96.0) and 76.7% (95% CI 53.7 to 90.3) of the patients with asymptomatic lumbar canal stenosis were free from leg symptoms for three and five years, respectively. There were no significant differences between the study and control groups in the recovery rate measured by the Japanese Orthopaedic Association score or improvement in the Nurick score at one year after surgery or at the final follow-up.

These results suggest that latent lumbar canal stenosis does not influence recovery following surgery for cervical myelopathy; moreover, prophylactic lumbar decompression does not appear to be warranted as a routine procedure for coexistent asymptomatic lumbar canal stenosis in patients with cervical myelopathy, when planning cervical surgery.

The scaphoid fracture is commonest in young men in the age group 15 to 29 years, who have the highest incidence of non-union, take the longest time to unite, lose more time from work, and spend the longest time as outpatients. A union rate of 95 per cent can be achieved using standard simple treatment. All but a few fractures are visible on the first radiograph, and failure of visualisation at this stage is not associated with a bad outcome. The postero-anterior and semipronated views are the most important to scrutinise. Crank-handle injuries have a particularly bad prognosis when they produce a transverse fracture of the waist of the scaphoid. Poor prognostic factors are displacement during treatment, the fracture line becoming increasingly more obvious, and the presence of early cystic change. The severity of trauma is an important factor to elicit from the history.

Ninety-five patients with steroid-induced avascular necrosis of bone have been personally treated by the author. Of these, eighteen had a lesion of the head of the humerus, on one or both sides. The conditions for which the steroids were given included post-transplantation, lupus erythematosus, glomerulonephritis and asthma. The characteristic lesion began as a subchondral osteolytic area which frequently progressed to collapse. The articular cartilage divided from the subchondral bone, either becoming detached as a free cap or at a later stage reattaching. In some cases the lesion was minimal and the symptoms were slight. Conservative treatment has consisted of pendulum exercises and avoidance of abduction, particularly against resistance. In fourteen patients this led to satisfactory function with only intermittent symptoms. Four patients required replacement of five humeral heads with Neer's prostheses. After one to seven years the results of all five were classified as excellent in terms of absence of symptoms and a free range of movement.

1. Early recognition of femoro-pelvic instability in proximal femoral dysplasia is essential to rational management.

2. Certain radiological signs helpful in identifying such patients within the first year are described.

3. Early operation is recommended to prevent displacement of a pseudarthrosis and to encourage healing. Alternative methods are described for established defects.

4. Radiological signs are described which indicate that healing without loss of femoro-pelvic stability will occur. Such patients may be managed expectantly.