Analysis of characteristics and reliability of different classification systems for evaluating coronoid process fractures in terrible triad injury / 中华创伤杂志

ABSTRACT

Objective:To analyze the types of ulnar coronoid process fractures in terrible triad injury (TTI) using three coronoid fracture classification systems and to explore the characteristics of coronoid process fractures and compare the reliability of different coronoid process fractures classification systems in TTI.Methods:A retrospective case series study was used to analyze the CT data of 43 patients with typical TTI admitted to First Affiliated Hospital of Fujian Medical University from January 2013 to October 2020. There were 26 males and 17 females, aged from 18 to 88 years [(41.8±15.6)years]. An independent three-dimensional model of the proximal ulna was established using the CT three-dimensional reconstruction technology. The characteristics of the coronoid process fractures were observed. The Regan-Morrey classification, O'Driscoll classification and Adams classification were used to classify the ulnar coronoid process fractures. The reliability of the three classification systems of coronoid fractures was analyzed.Results:The fracture line of the coronoid process was mostly located anterolaterally. Among all patients with ulnar coronoid fractures, there were 17 patients (40%) with type I, 19 (44%) with type II and 7(16%) with type III according to Regan-Morrey classification; there were 34 patients (79%) with type I, 2(5%) with type II and 7(16%) with type III according to O'Driscoll classification; there were 12 patients (28%) with type I, 3(7%) with type II, 7(16%) with type III, 18(42%) with type IV AL and 2(5%) with type IV AM according to Adams classification. Through reliability analysis, the Kappa coefficients of the inter-observer and intra-observer 1, 2, 3 of Regan-Morrey classification were 0.752, 0.813, 0.772 and 0.703, respectively; the Kappa coefficients of the inter-observer and intra-observer 1, 2, 3 of O'Driscoll classification were 0.797, 0.774, 0.837 and 0.775, respectively; the Kappa coefficients of the inter-observer and intra-observer 1, 2, 3 of Adams classification were 0.805, 0.835, 0.837 and 0.875, respectively.Conclusions:Most of the coronoid process fractures locate anterolaterally in TTI. Compared with Regan-Morrey classification and O'Driscoll classification, the reliability of Adams classification is best. Adams classification further subdivides the anterolateral fractures of the coronoid process, which may be more suitable in evaluating the classification of ulnar coronoid process fractures in TTI.