Outcomes According to Remnant Ligament Tissue Quality after Arthroscopic All-Inside Anterior Talofibular Ligament Repair for Chronic Ankle Instability

Category: Sports; Arthroscopy Introduction/Purpose: Arthroscopic all-inside techniques have gained prominence in the treatment of chronic ankle instability (CAI), offering effective solutions. However, arthroscopic treatment of CAI with poor remnant ligament-tissue quality is still controversy. This study aims to evaluate the outcomes of the arthroscopic all-inside anterior talofibular ligament (ATFL) repair, according to the quality of remnant ligament. Methods: A retrospective analysis was conducted on consecutive CAI patients who underwent arthroscopic ATFL repair, with a follow-up period of at least two years. Patients were categorized into two groups based on arthroscopic ATFL grade: Group G, characterized by good to moderate tissue quality with distension or discontinuity of the ATFL; and Group P, characterized by poor tissue quality with a hypoplastic ATFL. Patients with irreparable absent ATFL were excluded. Subjective outcomes were assessed using the visual analogue scale score, Foot and Ankle Outcome Score (FAOS), and the Karlsson ankle functional score. Objective outcomes included posturographic analysis and radiological evaluations, such as stress radiographs and axial view magnetic resonance imaging (MRI). Results: Among 163 patients, 22 were excluded based on predefined criteria, leaving 141 patients for analysis (Group G, n = 77; Group P, n = 64). Patients had a mean age of 32.1 years, and the average follow-up duration was 31.6 months. Both groups exhibited postoperative improvements in subjective and objective clinical outcomes (all p < 0.05). Significantly, Group P demonstrated lower FAOS scores in the sports unit (p = 0.016), an increased fall risk as determined by posturography at the final follow-up (p = 0.019), and a higher retear rate on axial view MRI (10.9%, 7/64) compared to Group G (2.6%, 2/77) (p = 0.044). Conclusion: Arthroscopic all-inside ATFL repair is an effective treatment for CAI, regardless of the quality of the remnant ligament. However, patients with poor ligament quality showed inferior clinical outcomes, especially in sports-related activities and proprioception. Additionally, they experienced a higher retear rate. These findings highlight the significance of performing arthroscopic all-inside ATFL repair selectively for CAI, considering the patient's activity level and the quality of the remaining ligament tissue.