Association Between Joint Effusion and Degenerative Osseous Changes of the Temporomandibular Joint: A Systematic...

Joint effusion (JE) on magnetic resonance imaging (MRI) has been proposed as a potential imaging marker of intra-articular inflammation and degenerative involvement in temporomandibular disorders (TMDs). However, its association with temporomandibular joint degenerative joint disease (TMJ-DJD) remains unclear.

A systematic search of PubMed, Scopus, Embase, Cochrane Library, and Web of Science was performed from inception to May 2026. Observational studies assessing MRI-detected JE and TMJ degenerative osseous changes in patients with TMDs were included. Pooled odds ratios (ORs) with 95% confidence intervals (CIs) were calculated. Heterogeneity was assessed using the I² statistic, and study quality was evaluated using the Joanna Briggs Institute checklist.

Eighteen studies involving 7001 TMJs were included in the systematic review, and 14 were included in the primary meta-analysis, which showed a positive association between MRI-detected JE and TMJ-DJD (OR = 1.41, 95% CI: 1.05-1.89; I² = 70.1%). A post hoc sensitivity analysis excluding Zheng et al. yielded an OR of 1.51 (95% CI: 1.16-1.97; I² = 63.4%). Marked effusion showed the strongest association with degenerative changes (OR = 2.63, 95% CI: 1.54-4.51). Subtype analyses suggested positive associations with flattening (OR = 1.49, 95% CI: 1.12-1.98) and osteophyte formation (OR = 1.61, 95% CI: 1.26-2.05), whereas findings for erosion and atrophy were inconclusive.

The available evidence suggests that MRI-detected JE is positively associated with TMJ degenerative osseous changes, particularly marked effusion, flattening, and osteophyte formation. JE may serve as an adjunctive imaging marker of degenerative joint involvement but should not be interpreted as a standalone indicator of TMJ-DJD.