Cementless hip arthroplasty in juvenile idiopathic arthritis.

Juvenile idiopathic arthritis (JIA) is the most common rheumatic disease in children. The hip is usually affected later, and its involvement is the most common cause of disability in JIA. Failure of medical and preventive treatment, significant joint destruction, or multiarticular involvement may necessitate total hip arthroplasty (THA) to restore good function. Related clinical trials show initially good THA results in most of the series, but long-term outcomes are uncertain due to a significant arthroplasty loosening rate in the initial years, particularly with cemented stems. The authors report the results of 62 noncemented THAs in 34 children with JIA after an average follow-up of 6 years (range 3-13). Mean age at surgery was 18.3 years (range 11.8-31) and 14 of the 34 children had active disease. Clinical results were good for hip function but less for global function. There were no infections. Two acetabular cups early in the series failed due to poor primary fixation and had to be revised. Survivorship analysis was performed with the Kaplan-Meier method. At 13 years, the survival rate was 100% for the femoral component and 90.1% for the acetabular component.