Diagnostic MRI imaging features of synovial chondromatosis of temporomandibular joint

Abstract To investigate the clinical and MRI features of synovial chondromatosis (SC) of the temporomandibular joint (TMJ). Fourteen patients with SC of TMJ were included. Clinical and MRI features were analyzed and divided into three types based on MRI classification: type I with loose bodies, type II with homogeneous masses and type III with a mixture of loose bodies and homogeneous masses. All SCs occurred in the superior compartment of the TMJ. There were 2 patients (14%) categorized as type I, 5 patients (36%) as type II and 7 patients (50%) as type III. Four patients (29%) had disc perforation, and 9 patients had bone erosion; among those 9, 7 patients (78%) had type III and 2 patients (22%) had type II. Histological examination showed inflammation in the synovial membrane and calcification, and cartilage of the hyaline type in all cases. MRI has advantages in the diagnosis of SC.