Extra-articular pigmented villonodular synovitis of the temporomandibular joint: case report and review of the literature.

Pigmented villonodular synovitis (PVNS) is a benign proliferative disorder of the synovial tissue, that usually affects the knee, ankle and other major joints. Involvement of the temporomandibular joint is, however, very rare. We describe a new case of recurrent PVNS arising from the temporomandibular joint that was classified as diffuse extra-articular type and was successfully treated surgically. The etiology and clinical features of PVNS are discussed and the previously reported cases in the literature are reviewed.