Arthroscopic synovectomy and postoperative assisted radiotherapy for treating diffuse pigmented villonodular synovitis of the knee: An observational retrospective study

Objective: This retrospective observational study aims to explore the treatment procedure and outcomes of arthroscopically assisted radiotherapy for diffuse pigmented villonodular synovitis (PVNS) of the knee joint. Methods: From September 2006 to August 2011, 28 diffuse PVNS patients were diagnosed and treated under arthroscopy. Twenty six underwent post-operative radiotherapy. All patients were followed up, and the average follow-up period was 54 months (range: 24 to 72 months). Results: All 26 patients who received external radiotherapy showed no recurrence at post-operative follow-up; The Lysholm knee joint function score increased from 54.3±9.0 at pre-operation to 71.2±6.7 at post-operation (paired t-test, t = −13.35, P 0.01). Conclusions: Arthroscopic synovectomy is an ideal treatment for PVNS of the knee. Adjuvant post-operative external radiotherapy prevents the recurrence of diffuse PVNS.