Additional Inferior Extensor Retinaculum Augmentation After All-Inside Arthroscopic Anterior Talofibular Ligament Repair for Chronic Ankle Instability Is Not Necessary

Background: Although several arthroscopic surgical techniques for the treatment of chronic ankle instability (CAI) have been introduced recently, the effect of inferior extensor retinaculum (IER) augmentation remains unclear. Purpose: To compare the clinical outcomes after arthroscopic anterior talofibular ligament (ATFL) repair according to whether additional IER augmentation was performed or not. Study Design: Cohort study; Level of evidence, 3. Methods: We performed a retrospective review of consecutive patients who underwent arthroscopic ATFL repair surgery for CAI between 2016 and 2018. The mean age of the patients was 35.2 years (range, 19-51 years), and the mean follow-up period was 32.6 months (range, 24-48 months). Patients were divided into 2 groups according to the surgical technique used for CAI: arthroscopic ATFL repair (group A; n = 37) and arthroscopic ATFL repair with additional IER augmentation (group R; n = 45). The pain visual analog scale, American Orthopaedic Foot & Ankle Society score, Foot and Ankle Outcome Score, and the Karlsson Ankle Function Score were measured as subjective outcomes, and posturographic analysis was performed using a Tetrax device as an objective outcome. Radiologic outcome evaluations were performed preoperatively and at 2 years postoperatively using stress radiographs and axial view magnetic resonance imaging (MRI). Results: Out of 101 patients, 19 (18.5%) were excluded per the exclusion criteria, and 82 were evaluated. We identified 6 retears (7.3%) based on postoperative MRI evaluation. All patients who had ATFL retear on MRI (8.1% [3/37] in group A and 6.7% [3/45] in group R) demonstrated recurrent CAI with functional discomfort and anterior displacement >3 mm as compared with the intact contralateral ankle. All clinical scores and posturography results were improved after surgery in both groups (P < .001). However, there were no significant differences in the clinical results and radiologic findings between the groups. Conclusion: The clinical and radiologic outcomes of patients with CAI improved after all-inside arthroscopic ATFL repair. However, additional IER augmentation after arthroscopic ATFL repair did not guarantee better clinical outcomes.