Severity of Soft Tissue Injury Within the Temporomandibular Joint Following Condylar Fracture as Seen on Magnetic Resonance Imaging and Its Impact on Outcome of Functional Management

Abstract

This study aimed to quantify articular soft tissue injury in condylar fractures based on magnetic resonance imaging (MRI) findings and investigate the impact of severity of articular soft tissue injury on the development of postoperative complications after functional reduction of a condylar fracture. Fifty-four patients 18 to 60 years old with unilateral undisplaced, deviated, or displaced condylar fractures were included in this prospective study. Articular soft tissue within the temporomandibular joint (TMJ) was evaluated using MRI within 7 days after the condylar fracture. Based on MRI findings, such injuries were classified as grade I (hemarthrosis only), grade II (hemarthrosis and disc displacement), grade III (hemarthrosis, disc displacement, and capsular tear), or grade IV (disc perforation in association with grade I, II, or III). All condylar fractures were treated conservatively using a standardized functional reduction method and patients were followed for 1 year. In 37 of 54 TMJs, MRI diagnosis of disc displacement was established, and capsular tear was observed in 12 joints and hemarthrosis was present in 42 joints. Disc perforation was present in only 5 cases. Patients with hemarthrosis alone (grade I) had the best outcome after functional reduction, whereas patients with hemarthrosis and disc displacement (grade II) had comparatively poorer results. Fifty percent of patients with grade II injury and 66.6% of patients with associated capsular tear (grade III) had limited mouth opening and restricted movement at the end of the follow-up period. One hundred percent of patients with disc perforation (grade IV) had restricted joint movement and joint noise. Results suggest that serious injury to the articular disc and capsule of the TMJ is a major contributing factor toward the development of complications after closed reduction of a condylar fracture.