Magnetic resonance imaging findings of internal derangement and effusion in patients with unilateral temporomandibular joint pain.

OBJECTIVES: The purpose of this study was to investigate the relationship between the presence of temporomandibular joint (TMJ) pain and the magnetic resonance (MR) imaging findings of internal derangement (ID) and effusion.

STUDY DESIGN: The study was comprised of 41 consecutive patients with TMJ pain. Criteria for including a patient were report of unilateral pain near the TMJ, with the presence of unilateral TMJ pain during palpation, function, and/or unassisted or assisted mandibular opening, and the absence of a specific clinical TMJ-related diagnosis of disk displacement with or without reduction. Bilateral sagittal and coronal MR images were obtained to establish the presence or absence of TMJ ID or effusion, or both.

RESULTS: Comparison of the TMJ side-related data showed a significant relationship between the clinical finding of TMJ pain and the MR imaging diagnoses of TMJ ID (P =.001), and TMJ effusion (P =.004). Furthermore, there was a significant relationship between the MR imaging diagnosis of TMJ ID and TMJ effusion (P =.000). Use of the kappa statistic test indicated poor diagnostic agreement between the presence of TMJ pain and the MR imaging diagnosis of TMJ ID (kappa = 0.34), TMJ effusion (kappa = 0.32), and TMJ ID and effusion (kappa = 0.27).

CONCLUSIONS: The study's findings suggest that although clinical pain is correlated with TMJ-related MR imaging findings, clinical pain in and of itself is not reliable for predicting the presence of TMJ ID or effusion, or both. Therefore, MR imaging appears to be a warranted and necessary supplement to the clinical findings.