The results of 75 total hip replacements in 42 children with juvenile chronic arthritis are reported after a mean follow-up of 5.4 years. Their ages ranged from 11 to nearly 17 years at operation and many had active disease. Severe pain and marked stiffness of the hips were limiting their independence. At least half of the children were still growing and continued to grow after operation. The patients were carefully selected and gratifying results were obtained, but pre-operative assessment and overall supervision by a rheumatologist are important. Technical difficulties related to the size and maldevelopment of the hip are discussed. There was no infection and the single case of loosening of a femoral component after nine years has been successfully revised.

Sixty-eight patients suffering deep infection from a consecutive series of 1746 total hip replacement operations are reviewed. The infection rate has been reduced considerably by improved technique and multiple antibiotic prophylaxis without the use of a special operation enclosure. Factors affecting deep infection are analysed and discussed.

We have reviewed 100 Attenborough total knee replacements in eighty-two patients with a follow-up of one to four years and conclude that this prosthesis has a valuable place in the surgical management of patients suffering from rheumatoid arthritis and osteoarthritis with severe involvement of the knee. In 85 per cent of these knees a good result was obtained with relief from pain, and in 77 per cent a useful range of movement with a stable knee. Only two patients with loosening and three with deep infection were seen in this series.

In fifty-six patients with ankylosing spondylitis three types of arthroplasty had been performed in ninety-nine hips. Forty-one of the patients were men and fifteen were women, their average age at operation being forty-two years. Primary pseudarthrosis produced well-satisfied patients, but only a fair result in five hips, whereas cup arthroplasty resulted in a poor outcome for eight hips, all of which needed revision. Total replacement of eighty-six hips, however, led to 73 per cent being graded as good or excellent up to ten years later. The main complications were deep infection of five hips, para-articular ossification around nine hips (six leading to bony ankylosis), and fibrous ankylosis of six hips.