Open Reduction Internal Fixation of Mandibular Condylar Fractures: Factors Influencing Radiographic Anatomical Reduction

Abstract

Mandible fractures occur frequently, accounting for approximately 70% of all facial fractures. Of those, fractures of the mandibular condyle account for 25-35%.1,2 Over several decades, there has been much controversy over the standard treatment method for condylar fractures, with increasing support for open reduction internal fixation (ORIF). The aim of this study is to determine negative and positive factors that may influence radiographic reduction outcomes after ORIF of mandibular condylar fractures.This retrospective study assessed the influence of several clinical factors on the quality of reduction. Records from patients treated with ORIF for condylar fractures between 2013 and 2021 at a single institution were reviewed. The predictor variables were condylar fracture level, type of fracture, amount and direction of displacement, vertical segment overlap, height of fracture, amount of soft-tissue envelope thickness, surgical approach, time to surgery, type of plate utilized, and surgeon experience. The primary outcome variable was the radiographic postoperative outcome of reduction and fixation as rated by 2 blinded observers in a 1-5 ordinal scale, with a score of 5 indicating adequate anatomical alignment of the posterior border of the mandibular-condylar border without displacement or deviation of the condylar process after ORIF.The data were analyzed statistically using ANOVA and Pearson's Correlation Coefficient tests using IBM SPSS Statistics to determine the significance between factors that may affect anatomical reduction and fixation of the mandibular condyle.The sample was composed of 21 subjects with 22 subcondylar fractures; 1 subject with bilateral subcondylar fractures was treated with ORIF with the majority being left subcondylar fractures (68%) with a concurrent fracture (86%). The study composed of nondisplaced (7), displaced (11), and dislocated (4) subcondylar fractures. The majority of subcondylar fractures treated with ORIF utilized 2 single miniplates (55%) via the retromandibular transparotid approach (90%). The mean adequacy of ORIF of subcondylar fracture score was 4.16 with the interclass correlation coefficient being 0.75, indicating good agreement between the 2 blinded observers. The plate utilized (P = .042), surgeon experience (P = .000), time to surgery (P =.000), and a concurrent mandible fracture (P = .000) were all shown to be significant in the adequacy of open reduction internal fixation of subcondylar fractures. A single plate along with a concurrent mandible fracture were shown to be negative factors influencing the ORIF of subcondylar fractures, whereas increased duration from the time of injury to ORIF was shown to be a positive factor.The management of condylar fractures is a subject of much debate and controversy within the field of oral and maxillofacial surgery. This study assessed multiple factors that may influence the objective radiographic outcome of ORIF of subcondylar fractures. Perhaps this study will further provide the oral and maxillofacial surgeon with an objective assessment based on radiographic interpretation for achieving anatomical reduction of the fractured condylar segment prior to taking the patient to the operative room.