Does joint effusion on T2 magnetic resonance images reflect synovitis? Comparison of arthroscopic findings in internal derangements of the temporomandibular joint

Abstract

Objective: The purpose of this study was to clarify the characteristics of joint effusion (JE) in the temporomandibular joint by comparing T2-weighted magnetic resonance (MR) images with arthroscopic findings.

Study design: MR images of 47 symptomatic temporomandibular joints (47 patients) with internal derangement associated with painful hypomobility were taken to evaluate the degree of JE on a scale of 0 to 3. Within 2 months after MR images, arthroscopic findings with respect to the severity of synovitis, adhesion, and degenerative change in the superior compartment were each quantitatively assessed on a scale of 0 to 10. The arthroscopic scores were compared among the 4 JE grades, as well as between 2 groups, effusion-present (grades 2 and 3) and effusion-absent (grades 0 and 1), by using the Spearman correlation coefficient and the Mann-Whitney U test.

Results: The distribution of JE was as follows: 10 joints had grade 0, 5 joints had grade 1, 19 joints had grade 2, and 13 joints had grade 3. The synovitis score had a significant relationship to the degree of effusion (P =.0012) and was higher in the effusion-present group (6.4 +/- 2.0) than in the effusion-absent group (4.2 +/- 1.6) (P =.0005) On the other hand, there was no statistically significant correlation between either adhesion or degenerative change and effusion.

Conclusions: JE may reflect synovitis; however, the nature of JE itself needs to be further elucidated by additional studies.