[Replacement of hip joints with total endoprostheses in patients with ankylosing spondylitis].

In the Rheumatological Institute in Prague the authors made a retrospective investigation in patients with ankylosing spondylitis affecting the hip joints where one or two endoprostheses of the hip joints were made. In all these patients they evaluated the subjective complaints of the operated extremity, they made a clinical examination of the extent of mobility and evaluated X-ray pictures. The group of 20 patients was examined in this retrospective investigation approximately five years after operation. From the total of 32 endoprostheses 20 were cemented and 12 were without cement. From the total number of patients only four reported slight pain in the area of the operated hip joint without signs of loosening on the X-ray picture. The extent of mobility of all endoprostheses was very satisfactory, the mean abduction in men was 27.6 degrees, in women 30.7 degrees, flexion 84 degrees in men and 97 degrees in women. As revealed by X-ray, the hip joints were affected most frequently by coxitis, osteoplastic changes were detected in six patients. Enthesopathies of a small or medium extent were found in almost all patients. Heteroplastic bone was evaluated according to Brooker's criteria, in the investigated group only type I was found. It may be stated that the submitted group of results of endoprostheses in ankylosing spondylitis is a very satisfactory solution which improves the patient's mobility and thus restores the quality of life.