A case of synovial chondromatosis of the temporo-mandibular joint.

Synovial chondromatosis is a well-known clinical entity and has been recorded not only in large joints such as the knee, hip, shoulder, elbow and ankle, but also in the carpus, tarsus and finger. No reference could be found to its occurrence in the temporo-mandibular joint andfor this reason it may be of interest to record the following case: A woman, aged 63 years, was seen in March 1951 with a four months' history of intermittent pain and stiffness of the right temporo-mandibular joint. The joint would lock suddenly and be painful, but would unlock with equal suddenness and with relief of pain. At other times a click was felt in the joint. Examination showed that the region of the joint was swollen; movement was limited and associated with coarse creaking. Radiographs showed distension of the joint and erosion of the cranial surface (Fig. i); no loose bodies could be detected. The diagnosis of internal derangement was made without difficulty. In May I95I the joint was explored through an L-shaped incision. On opening the capsule much synovial fluid escaped, together with many hard pearly-white cartilaginous loose bodies varying in size from a pea to a pin-head (Fig. 2). All of these came from the superior compartment of the joint, FIG. 2.-The loose bodies removed from the superior compartment of the right temporomandibular joint, life size. Some were in clumps; when separated there were fortyeight in all.