Long-term results of surgical treatment of pigmented villonodular synovitis of the knee

Objectives: The aim of this study was to evaluate the long-term results of total synovectomy in pigmented villonodular synovitis of the knee (PVNS). Methods: Open total synovectomy was performed for 19 patients (9 men, 10 women; mean age: 42.8 years) with PVNS. Of these patients, 15 had diffuse and 4 localized PVNS. The patients were followed for an average of 80.2 months and the average time between the onset of complaints and surgery was 23 months. In 4 patients, PVNS was identified during total knee replacement (TKR) performed due to gonarthrosis. Radiotherapy was performed as an adjuvant treatment in one patient with recurrence. Puncture was performed in 11 patients due to effusion and 8 to 70 cc of fluid was aspirated. Diagnosis was made during the exposure for TKR in 4 patients, by a biopsy in 2 and based on joint puncture and MRI findings in the rest. Results: Recurrence occurred in 5 patients. A second total synovectomy was performed in 4 patients. Radiotherapy was used for the remaining one patient. Two patients were operated three times. During the follow-up, TKR was performed in 7 of the 19 patients. None of the patients developed infection and hemarthrosis requiring puncture nor required amputation or arthrodesis. Three patients had a postoperative knee joint stiffness of 10 to 25 degrees. The patients were evaluated according to the Knee Society Score and 8 (42.2%) had perfect, 9 (47.3%) good and 2 (10.5%) bad results. Conclusion: PVNS is a disease with a high risk of recurrence. No individual or combined treatment method can offer a definitive solution. Open or arthroscopic radical synovectomy is still considered as the gold standard. If necessary, adjuvant intraarticular or extraarticular radiotherapy can be added to the treatment.