Risk Factors Associated With Poor Outcomes Following Temporomandibular Joint Discectomy and Fat Graft.

ABSTRACT

PURPOSE: Temporomandibular joint (TMJ) discectomy is performed for patients with degenerative joint disease with an unsalvageable disc, but with a salvageable condylar head and glenoid fossa. The purpose of this study was to estimate the incidence and risk factors associated with poor postoperative outcomes following TMJ discectomy and abdominal fat grafting. METHODS: A retrospective cohort study was conducted on patients who underwent TMJ discectomy. Included in this study were patients who had complete data sets with a minimum of 1-year follow-up. Potential risk factors included demographics, preoperative findings (mouth opening, pain levels, previous TMJ surgery), operative findings (disc degeneration, state of TMJ components), and postoperative outcomes (pain levels, mouth opening). Failed outcomes were those who had return of pain postoperatively, no improvement in mouth opening following TMJ discectomy, and/or those who progressed to TMJ total joint replacement (TJR). Statistical methods included Kaplan-Meier curves and Cox proportional hazards regression time to event analyses. RESULTS: This study included 129 patients who had undergone 132 TMJ discectomies. Most patients were female (89.9%), with a mean age of 43.2 years, standard deviation 14.2. The success rate for discectomy was 75.2% and the conversion rate of TMJ discectomy to TJR was 11.7%. A total of 32 patients (24.8%) experienced return of pain. The median time to return of pain or second surgery was 94.4 months (95% CI = 88.3 to 101.8). No risk factors were statistically significant, although mouth opening improvement of less than 10% was associated with higher risk of poor outcome (P = .77). CONCLUSION: The findings of this study suggest that lower improvement in mouth opening at 1 year following surgery is likely to result in failure of the TMJ discectomy procedure although the result was not statistically significant. This outcome may ultimately necessitate a TJR.