A Novel Classification Method of Zygomaticomaxillary Complex Fractures by Suture Comminution to Better Predict Clinical Outcomes

Abstract

Purpose: To assess a novel technique for classifying zygomaticomaxillary complex (ZMC) fractures by its ability to predict clinical outcomes and reoperations when compared to a well-established classification method. Methods: The investigators conducted a retrospective cohort study over a 7-year period composed of patients with unilateral and bilateral fractures of the ZMC. Fractures were graded according to the Zingg method and a CT-based comminution method. Outcomes were classified into 3 groups: orbital complications, facial complications, and reoperation. Orbital complications consisted of enophthalmos and diplopia. Facial complications consisted of lagophthalmos, ectropion, ptosis, facial motor weakness, trismus, and malar depression. Other variables included demographics, mechanism of injury, and preoperative symptoms. Results: A total of 159 patients were identified producing a total of 204 ZMC fractures. The mean age was 40.2 ± 16.5 years and the most common mechanism of injury was motor vehicle accidents in 49.7% of patients. By the Zingg classification, B-type fractures were the most common in 46% of patients. The average total comminution score was 2.9 ± 2.4. Univariate analysis showed an association between increased age and reoperation ( P = .01). After adjusting for demographic and clinical variables on multivariate analysis, total comminution score was a significant predictor of facial complications and reoperation. The Zingg method did not demonstrate significance as a predictor for facial complications or reoperation. Neither classification method was predictive of orbital complications. Conclusion: The results of this study suggest that total comminution scoring is a viable method for categorizing ZMC fractures to better predict clinical outcomes.