All-Inside Arthroscopic Lateral Capsular Shift for Chronic Lateral Ankle Instability With Poor Ligament Remnants: A Retrospective Comparative Study With the Arthroscopic Modified Bröstrom Procedure.

The arthroscopic modified Bröstrom procedure (AMBP) is widely used to treat chronic lateral ankle instability (CLAI). However, in patients with poor or absent ligament remnants, the outcomes may be suboptimal, suggesting a clinical need for alternative techniques. To introduce all-inside arthroscopic lateral capsular shift (ALCS) and compare outcomes with those for AMBP. Cohort study; Level of evidence, 3. We retrospectively analyzed 132 patients (139 ankles) with CLAI who underwent all-inside arthroscopic procedures between November 2017 and December 2022 and had a minimum follow-up of 24 months: 88 ankles with good ligament remnants underwent AMBP, and 51 ankles with poor or absent ligament remnants underwent ALCS. Clinical outcomes were evaluated using visual analog scale pain scores and Foot and Ankle Outcome Scores. Radiological outcomes were evaluated by anterior displacement of the talus and talar tilt angle. Between-group comparisons were performed using parametric or nonparametric tests, with significance set at a P value <.05. The 2 groups were comparable in baseline demographics, including age, sex distribution, and follow-up duration, with no significant differences between groups. The mean follow-up was 41.5 months (range, 24-89 months). For both groups, functional scores improved significantly after surgery, with no significant differences between groups in final scores or the proportion of patients who achieved functional score improvements exceeding the minimal important change (all P > .05). Final radiological parameters and degree of correction were also comparable between groups. No significant differences between groups were observed for overall complication rates (P = .725), with 5.7% (95% CI, 2.5%-12.6%) for AMBP group and 7.8% (95% CI, 3.1%-18.5%) for ALCS group, and recurrent instability (P > .999), occurring in 2.3% (95% CI, 0.6%-7.9%) of ankles (n = 2) in AMBP group and in 2.0% (95% CI, 0.3%-10.3%) of ankles (n = 1) in ALCS group. Our study showed that ALCS achieved clinical and radiological outcomes comparable to those of AMBP, with low recurrence rates after at least 2 years of follow-up. Our results suggest that ALCS may be a viable operative treatment option for patients with CLAI but poor ligament remnants. Future prospective studies are needed to further validate and generalized the findings of this study.