Arthroscopic punch for definitive diagnosis of synovial chondromatosis of the temporomandibular joint. Case report and pathology review.

Synovial chondromatosis is characterized as a benign monoarticular condition with metaplastic cartilaginous nodules that develop within the synovial membrane of articulating joints. In addition to a pathology literature review, this article describes an unusual case of temporomandibular synovial chondromatosis that was sufficiently expansile to displace the condyle, which created not only a posterior occlusal apertognathia, but unusual articular bony fossa and eminentia erosions. An arthroscopic approach for definitive diagnostic punch biopsy and surgical approach is described and presented along with preoperative computerized tomograph, magnetic resonance imaging, and tomographic diagnostic images, as well as 3-year follow-up clinical and radiographic findings. Most interestingly, the arthroscopic examination and biopsy proved to be the most useful method to establish a definitive diagnosis of synovial membrane chondromatosis within the temporomandibular joint region for this patient.