Analysis of Pre- and Postoperative Magnetic Resonance Imaging and Functional Status in Anterior Talofibular Ligament Injury Managed with Arthroscopic Modified Broström Procedure

Abstract

The arthroscopic modified Broström procedure (aMBP) with internal bracing has become an increasingly favored surgical option for managing anterior talofibular ligament (ATFL) injuries, particularly due to its potential to expedite return to daily activities and sports. However, the intrinsic quality of the ATFL and surrounding tissue remains a critical prognostic factor for successful anatomic repair. Magnetic resonance imaging (MRI) offers a noninvasive and powerful tool for evaluating ATFL integrity and associated intra-articular pathology. In particular, T2-weighted MRI signal intensity has been shown to correlate inversely with ligament biomechanical strength. This study aimed to examine the relationship between MRI-based ligament characteristics and postoperative clinical outcomes in patients undergoing aMBP for ATFL injury. A retrospective analysis was conducted on 100 patients with confirmed ATFL injuries who underwent aMBP with internal bracing. Preoperative and 6-month postoperative MRI scans of the injured ankle were reviewed. Functional assessment was performed using the American Orthopaedic Foot and Ankle Society (AOFAS) score at baseline, 2 months, and 6 months postoperatively. ATFL morphology was categorized as wavy-shape or discontinuity on preoperative MRI. Radiographic parameters, including talar tilt angle and anterior talar translation, were also evaluated. Both morphological groups demonstrated statistically significant postoperative improvements in AOFAS scores, talar tilt angles, and anterior talar translation ( P <.05). At 6 months postoperatively, all repaired ATFLs exhibited a continuous linear band structure on MRI, and 64.9% (63 of 97) demonstrated low signal intensity on T2-weighted sequences. The continuity group had a significantly higher prevalence of low signal intensity compared to the discontinuity group (80.9% vs. 50.0%, P < 0.05). aMBP with internal bracing effectively improved functional and radiological outcomes across all morphological subtypes. However, better preoperative ATFL morphology exhibited more favorable postoperative MRI characteristics, suggesting a higher capacity for biological healing and ligament maturation.