Ligament Advanced Reinforcement System (LARS) Augmented Repair vs Autograft Reconstruction for Chronic Lateral Ankle Instability: A Retrospective Comparative Study

Background: Both autograft reconstruction and Ligament Advanced Reinforcement System (LARS) augmented repair are used for chronic ankle instability (CAI), but comparative evidence regarding postoperative recovery remains limited. This study compared recovery trajectories and functional outcomes between these techniques over 24 months. Methods: A total of 112 patients with CAI undergoing LARS augmented repair (n = 54) or autograft reconstruction (n = 58) were retrospectively analyzed. Primary outcomes were the Foot and Ankle Outcome Score Sport and Recreation subscale (FAOS-Sport) and Tegner activity score. Secondary outcomes included other FAOS subscales and visual analog scale (VAS) pain scores. Outcomes were assessed preoperatively and at 1, 3, 6, 12, and 24 months postoperatively; VAS was not assessed at 24 months. Longitudinal recovery trajectories were analyzed using generalized estimating equations, and an exploratory FAOS-based minimal clinically important difference (MCID) responder analysis was performed. Results: All outcomes improved significantly over time (all P < .001). Compared with the autograft group, the LARS group demonstrated higher FAOS-Sport and Tegner scores at 1, 3, and 6 months (all P < .001), indicating faster early functional recovery. Similar early advantages were observed in secondary outcomes, but between-group differences were no longer evident at 12 and 24 months. In the exploratory MCID analysis, a greater proportion of LARS patients achieved the FAOS MCID at 3 months, whereas all available patients in both groups reached the threshold by 6 months. Conclusion: Both LARS augmented repair and autograft reconstruction were associated with improved functional outcomes over time. LARS was associated with faster early recovery, whereas differences diminished over time and no significant between-group difference could be detected in the outcomes available by 24 months. LARS may be considered for patients prioritizing early functional recovery. Level of Evidence: Level III, retrospective comparative study.