Fig. 4From: Multifocal pigmented villonodular synovitis coexisting in both the knee joint and the patella: a case report and literature reviewArthroscopic images (a, b) of the left knee indicating prolific synovium with coarse villi, heavily pigmented diffuse pigmented villonodular synovitis. No communicating link was found under arthroscopic observation (c). Although the chondromalacia changes are visible on the articular surface of patella, it seems exactly intact without any eroded hole (d)Back to article page