MRI characteristics of rheumatoid arthritis in the temporomandibular joint

Objectives: The aim of this study was to investigate characteristic MRI findings of rheumatoid arthritis (RA) in the temporomandibular joints (TMJs). Methods: 61 patients (122 TMJs) with RA in the TMJ and 50 patients (100 TMJs) with temporomandibular disorder (TMD) were included in this study. MR images of these patients were assessed by two oral radiologists for the presence or absence of osseous changes, disc displacement, joint effusion and synovial proliferation. These findings were compared between the two patient groups. Results: Osseous changes in the condyle and articular eminence/fossa in the RA patient group were significantly more frequent than in the TMD patient group, and were often very severe. Joint effusion was also significantly more frequent in the RA patient group. Synovial proliferation was found in all TMJs in the RA patient group, whereas it was very uncommon in the TMD patient group. Conclusions: Severe osseous changes in the condyle and synovial proliferation were considered characteristic MRI findings of RA in the TMJs. Dentomaxillofacial Radiology (2013) 42, 31627230. doi: 10.1259/dmfr/31627230