Two incision synovectomy and radiation treatment for diffuse pigmented villonodular synovitis of the knee with extra-articular component

Diffuse pigmented villonodular synovitis (PVNS) of the knee is a rare, locally aggressive disease. Since 1995 the senior author has been treating patients with diffuse intra- and extra-articular PVNS of the knee with a bimodality treatment protocol, consisting of anterior and posterior open synovectomies in conjunction with external-beam radiation. The purpose of this study was to describe the surgical technique, evaluate our protocol's efficacy in limiting local recurrences, and assess its functional implications and associated morbidities. The medical records of nine consecutive patients were analyzed. Functional results were measured using the Knee Society score. The mean follow-up was 67 months (range 37-103 months). Eight patients were disease free and one patient had local recurrence, which was extra-articular, localized and non-progressive. The mean knee rating and functional rating had significantly improved from 65.2 and 70 preoperatively to 93.7 and 96.6 postoperatively respectively. Maximal knee flexion ranged from 90° to 130°, and only 3 patients developed flexion contractures of 5°. In conclusion our bimodality protocol of anterior and posterior open synovectomies, in conjunction with external-beam radiation, limited the recurrence of diffuse intra- and extra-articular PVNS of the knee. All patients showed good-to-excellent functional outcomes and were able to return to their previous level of activity.