Temporomandibular joint synovial chondromatosis

Objective: To investigate the diagnosis and treatment procedure of synovial chondromatosis (SC) of the temporomandibular joint (TMJ). Methods: Clinical features, imaging features, surgical methods, and prognosis of 7 patients with SC of the TMJ were analyzed. We also reviewed and analyzed surgery-relevant literature included in the Pubmed database in the past decade using the search terms “synovial chondromatosis” and “temporomandibular joint”, and found 181 cases. Results: There was no specific difference in the symptoms of SC in the TMJ in different Milgram’s stages in our cases and the cases mentioned in the literature. The main symptoms of SC in the TMJ were pain (100%, 7/7; 64.64%, 117/181), limited mouth opening (57.14%, 4/7; 53.59%, 97/181), swelling (14.29%, 1/7; 28.18%, 51/181), crepitus (28.57%, 2/7; 19.34%, 35/181), and clicking (14.29%, 1/7; 9.94%, 18/181) in our cases and cases from literature separately. The imaging features of SC were occupying lesions (including loose bodies or masses) (71.42%, 5/7; 37.57%, 68/181), bone change in condyle or glenoid fossa (1/7, 14.29%; 34.81%, 63/181), effusion (42.86%, 3/7; 20.99%, 38/181), joint space changes (42.86%, 3/7; 11.05%, 20/181) in our cases and cases from literature separately. The surgical procedures seem to depend mainly on the involved structures and the extension of the lesion rather than the Milgram’s stage. Conclusions: The clinical features of SC in the TMJ are nonspecific and easy to be misdiagnosed. MRI is helpful in the diagnosis of SC in the TMJ. The surgical procedures mainly depend on the involved structures and the extension of the lesion.