Bipolar hemiarthroplasty in juvenile rheumatoid arthritis: long-term survivorship and outcomes.

Because controversy surrounds the management of end-stage hip disease in juvenile rheumatoid arthritis (JRA), this study evaluated the long-term outcome of bipolar hemiarthroplasty as an alternative to conventional joint arthroplasty. A total of 24 JRA patients underwent 39 hemiarthroplasties; follow-up averaged 12 years (range, 3 to 15 years). There were 14 hips (36%) revised, and 25 hips (64%) maintained the original components. Mean Harris hip scores in surviving hips improved from 29 to 69 points (P<.001). Radiographs showed progressive bipolar superomedial migration (P<.01) despite attempted augmentation. Failure defined as revision to total hip arthroplasty or definite radiographic loosening occurred in 15 hips (38%). Ten-year Kaplan-Meier survivorship for all prostheses was 78%. Independent multivariate risk factors for failure included acetabular grafting (P =.006), prosthesis type (P<.001), and unilateral replacement (P<.001).