Parotid Lymphadenopathy Is Associated With Joint Effusion in Non-Neoplastic Temporomandibular Disorders.

PURPOSE: Lymphadenopathy often occurs in the setting of inflammation, with or without infection. We sought to elucidate any association of parotid lymphadenopathy with joint effusion in temporomandibular joint (TMJ) disorders. MATERIALS AND METHODS: We performed a retrospective cohort study. We analyzed the magnetic resonance imaging studies of patients with suspected TMJ disorders performed from April 2006 to March 2007. The degree of joint effusion was graded on sagittal T2-weighted spin echo images according to a commonly used system. On axial short T1-weighted short inversion recovery images, the number and short-axis diameter of the parotid lymph nodes were recorded. We performed analyses of the cluster-correlated data using the Mann-Whitney U test and Spearman's correlation coefficients. P < .05 was considered to indicate significance. To assess the possible predictive value of certain variables, a generalized linear model (generalized estimation equation) was constructed, considering the multiple measurements. RESULTS: A total of 402 TMJ disorders were analyzed from 201 patients during the study period. The number and size of the parotid lymph nodes identified was significantly greater in the patients with TMJ effusion (P < .01) than in those without effusion. CONCLUSION: In the present study, we found an association between parotid lymphadenopathy and joint effusion in TMJ disorders. These findings indicate that lymphadenopathy should be considered as an inflammation condition commonly associated with joint effusion in TMJ disorders.

Characteristic Magnetic Resonance Imaging Findings in Rheumatoid Arthritis of the Temporomandibular Joint: Focus on Abnormal Bone Marrow Signal of the Mandibular Condyle, Pannus, and Lymph Node Swelling in the Parotid Glands.

PURPOSE: The purpose of this study was to determine the characteristic magnetic resonance imaging (MRI) findings indicating bone and soft tissue involvement in patients with rheumatoid arthritis (RA) of the temporomandibular joints (TMJs). PATIENTS AND METHODS: Twenty-one patients with RA and TMJ pain who underwent MRI examination of the TMJs at the authors' hospital from August 2006 to December 2014 were included in this study. Twenty-two patients with normal TMJs who underwent MRI examination at the authors' hospital from November to December 2014 were included as controls. MRI findings were compared between the 2 groups. RESULTS: MRI findings of RA in the TMJ included 1) abnormal disc position (95.2%), 2) abnormal disc morphology (83.3%), 3) joint effusion (30.9%), 4) osseous changes in the mandibular condyle (83.3%), 5) synovial proliferation (pannus; 85.7%), 6) erosion of the articular eminence and glenoid fossa (9.52%), 7) deformity of the articular eminence and glenoid fossa (16.6%), 8) abnormal bone marrow signal in the mandibular condyle (83.3%), and 9) swelling of lymph nodes in the parotid glands (78.5%). The abnormal bone marrow signal and pannus in the mandibular condyle and lymph node swelling in the parotid glands were markedly more common in patients with RA than in controls. CONCLUSIONS: MRI findings of RA of the TMJs were characterized by bone and soft tissue involvement, including abnormal bone marrow signal of the mandibular condyle, pannus, and swelling of lymph nodes in the parotid glands. These characteristic MRI findings could be useful in detecting RA in the TMJ in a clinical situation.