MRI-detected joint effusion and disc displacement without reduction as independent predictors of pain in intraarticular temporomandibular joint disorders.

INTRODUCTION Intraarticular temporomandibular joint (TMJ) disorders are a leading cause of orofacial pain, but whether MRI findings predict symptoms remains unclear.

Materials And Methods

This retrospective study included 79 patients (158 TMJs) with intra-articular TMJ disorders. Predictors included disc displacement (DD), joint effusion grade (0-3), disc morphology, and osseous changes. Outcomes included pain severity (VAS), clicking, and crepitation.

Results

DD without reduction predicted higher pain severity (OR=2.51; p= .014). Effusion showed a dose-response relationship with pain across all grades (Grade 1: OR=3.23; Grade 2: OR=4.18; Grade 3: OR=8.93; p≤ .004), independent of DD type. Crepitation was most prevalent in Grade 1 effusion joints (23.6%), even without osseous changes.

Conclusion

Joint effusion independently predicts pain severity in intraarticular TMJ disorders, distinct from DD type. Crepitation linked to mild effusion without osseous changes suggests it may not exclusively indicate end-stage degeneration. Effusion grading should be prioritized in MRI-based diagnosis.