Diagnosing TMJ internal derangement and osteoarthritis with magnetic resonance imaging

Background. The authors conducted a study to investigate the relationship b etween the presence of temporomandibular joint, or TMJ, paint and magnetic resonance imaging, or MRI, findings of internal derangement, or ID, and art hritis, or OA. Methods. The authors studied 131 consecutively seen TMJ pain patients. Thei r criteria for including a patient in the study were report of unilateral o rofacial pain referred to TMJ and the presence of unilateral TMJ pain durin g palpation, function, and unassisted or assisted mandibular opening. The a uthors took bilateral sagittal and coronal MRIs to establish the presence o r absence of TMJ ID, OA or both. Results. When the authors compared TMJ side-related data from all subjects, they found a significant relationship between the clinical findings of TMJ pain and the MRI diagnoses of TMJ ID (P = .000) and TMJ OA (P = .013). The y also found a significant relationship between the MRI diagnosis of TMJ ID type and that of TMJ OA (P = .000). The authors used the kappa statistical test and found poor diagnostic agreement between the presence of TMJ pain and the MRI diagnosis of TMJ ID (kappa = 0.21), TMJ OA (kappa = 0.15), and TMJ ID and OA combined (kappa = 0.18). Conclusions. The study's findings suggest that while clinical pain is relat ed to TMJ-related MRI findings, the presence of clinical pain is not a reli able predictor of TMJ, ID, OA or both. Clinical Implications. Using MRI to supplement clinical findings of TMJ pai n appears warranted and necessary to establish the presence or absence of T MJ ID.