Pigmented Villonodular Synovitis of the Hip: A Systematic Review.

Pigmented villonodular synovitis is a rare proliferative condition of the synovium that affects large joints. The primary treatment options are synovectomy and a combination of synovectomy and arthroplasty. We performed a systematic review of the literature, excluding all nonclinical and review articles with follow-up of less than 2 years. Primary outcomes reported were disease recurrence, symptom progression, and revision surgery. Student t tests were used to compare outcomes after synovectomy with outcomes after synovectomy combined with arthroplasty. Twenty-one studies (82 patients) were included. All represented level IV or V evidence. Fifty-one patients (59.3%) were female. Mean (SD) age was 33.2 (12.6) years. Synovectomy alone was performed in 45 patients (54.9%), and synovectomy with arthroplasty was performed in 37 patients (45.1%). Mean (SD) follow-up was 8.4 (5.9) years. The groups' revision rates were not significantly different (26.2% vs 24.3%; P = .17). Mean (SD) time to revision was significantly (P = .02) longer in the synovectomy-with-arthroplasty group, 11.8 (4.5) years, than in the synovectomy-only group, 6.5 (3.9) years. Study results showed revisions are common after surgery for hip pigmented villonodular synovitis, affecting 1 in 4 patients regardless of which surgery they have-either synovectomy alone or synovectomy combined with arthroplasty. Revision is required sooner in synovectomy-only patients than in patients who also undergo arthroplasty.