We studied 29 girls and one boy with adolescent idiopathic scoliosis who were at Risser grade 0 at the time of posterior spinal fusion and were followed until maturity (mean 7.8 years). We used serial radiographs to measure the ratio of disc to vertebral height in the fused segments and to detect differential anterior spinal growth and assess its effect on scoliosis, vertebral rotation, kyphosis, and rib-vertebral-angle difference (RVAD). From one year after surgery to the latest review, the percentage anterior disc height decreased by nearly one-half and the percentage posterior disc height by nearly one-third in the fused segments (p < 0.001). There was a 4 degree increase in mean Cobb angle (p < 0.001), 11 patients (37%) having an increase of between 6 degrees and 10 degrees. There was a significant increase in mean apical rotation by 2 degrees (p = 0.003), and four patients (13%) had an increase of between 6 degrees and 16 degrees. There was little change in kyphosis. There was an increase in mean RVAD by 4 degrees (p = 0.003), seven patients (23%) showing a reduction by 1 degree to 7 degrees, and 11 (37%) increases of between 6 degrees and 16 degrees. Spinal growth occurs after posterior fusion in adolescents who are skeletally immature, as a result of continued anterior vertebral growth. There is some progression of scoliosis, vertebral rotation, and RVAD, but little change in kyphosis. The increase in deformity is not enough to warrant the use of combined anterior and posterior fusion. The findings are relevant to the management of progressive curves, the timing and extent of surgery, and the prognosis for progression of deformity in this group of patients.

We have used dual-energy X-ray absorptiometry to measure bone mineral density (BMD) in patients with ankylosing spondylitis comparing 41 healthy control subjects and 33 patients with either mild or advanced ankylosing spondylitis. A Norland XR-28 bone densitometer was used to measure the BMD of the lumbar spine and that of the head, trunk, arms, femoral neck, Ward's triangle, legs, pelvis, and total body. Mild ankylosing spondylitis was defined as that showing no or incipient syndesmophytes between L1 and L5 vertebrae: we studied 16 men of mean age 37 years and six women of mean age 37 years. Advanced ankylosing spondylitis, in 11 men of mean age 42 years, showed a bamboo spine with bridging syndesmophytes across all disc spaces between L1 and L5. The mean BMD of the lumbar spine was significantly different in the patients and control subjects of the same sex (0.01 < p < 0.05, analysis of variance), being significantly reduced compared with control subjects in mild disease (0.001 < p < 0.01, t-test) and significantly increased in advanced disease over control subjects (0.01 < p < 0.05; t-test) and over patients with mild disease (0.001 < p < 0.01; t-test). The relevance of these findings to the aetiology and pathogenesis of spinal deformities and other complications in ankylosing spondylitis is discussed.

We have reviewed 80 children who were involved in the Medical Research Council (UK) trial of surgical treatment for tuberculosis of the spine in Hong Kong. Radical surgery or debridement had been performed at mean ages of 7.6 years (n = 47) and 5.1 years (n = 33) respectively. The patients were followed up to skeletal maturity (mean 17 years). Spinal deformity was measured on lateral radiographs taken preoperatively, at six months, one year, five years and at final follow-up. Radical surgery and grafting produced a reduction in kyphos and deformity angles at six months; this correction was maintained during the growth period. By contrast, after debridement surgery there was an increase in deformity at six months, with a tendency to some spontaneous correction during the growth period. There were statistically significant differences between angles for the radical and debridement groups only at six months postoperatively, but the changes during later follow-up were similar in the radical and debridement groups. Our findings highlight the importance of the surgical correction of deformity, and provide no evidence to suggest that disproportionate posterior spinal growth contributes to progression of deformity after anterior spinal fusion in children.

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.

The factors involved in the mechanism leading to traumatic posterior dislocation of the hip are examined. In 47 adult patients who had previously suffered such a dislocation, ultrasound scans were used to measure femoral anteversion on both the affected and the uninjured side. In 36 normal adult volunteers, used as controls, similar measurements were made. Femoral anteversion on both the injured and uninjured side was significantly reduced in the patients compared with the volunteers. These findings are discussed in the light of previous work which indicates that medial rotation is a factor in the mechanism of posterior dislocation of the hip. It is suggested that reduced anteversion acts like medial rotation to make the hip more susceptible to posterior dislocation, and that the less the anteversion the more likely is the injury to be a dislocation rather than a fracture-dislocation. It is concluded that patients who suffer such dislocated hips belong at one extreme of the normal population, having either reduced femoral anteversion or even retroversion, and that this anatomical feature selects towards hip dislocation rather than to injury of the femoral shaft, knee or tibia during the appropriate type of accident.

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.

The measurements of the angle of anteversion of the femoral neck by ultrasound scanning is described. The method was compared with direct measurement in 30 dried femora, and was then used in 18 normal volunteers and eight patients. The method is non-invasive, accurate and easily applicable. Findings in normal subjects included variation of the angle of anteversion from 10 to 34 degrees with a maximal difference between sides of six degrees. The expected rotational deformity of the femur was found in patients with unilateral intoeing.

Out of a total of 91 patients with traumatic posterior dislocation of the hip treated between 1936 and 1974 in the Mansfield area, 81 patients were reviewed. The average follow-up period was 12.5 years, although there was a large number of cases with a follow-up of more than 15 years and a smaller number with a follow-up of 30 years. The overall results were surprisingly poor despite early reduction of the dislocation in the majority of cases. We found that 15 years after simple dislocation 24 per cent of the cases had a poor result by both clinical and radiological criteria, but in the more severe grades of initial injury the results became worse, with 73.3 per cent of the patients graded as fair and poor, and only 26.7 per cent graded excellent or good.