Synovial chondromatosis of the TMJ: MR and CT findings.

Synovial chondromatosis is a rare , benign joint disorder characterized by metaplasia of the synovium with the formation of numerous foci of cellular hyaline cartilage. These foci may detach from the synovium and become loose bodies within the joint space, and also may calcify. The disease is usually monoarticular, of unknown origin, and occurs most often in larger joints, such as the knee, shoulder, and hip [1 , 2] . Synovial chondromatosis of the temporomandibular joint (TMJ), first described by Axhausen in 1933 [3], is truly rare , with only 41 cases reported in the literature [3-7]. This article presents another case, and emphasizes MR and CT findings.