Excellent functional outcomes without physeal violation after arthroscopic all-inside ligament repair for ankle instability in skeletally immature patients.

PURPOSE: Arthroscopic all-inside ligament repair is a widely used technique for treating chronic lateral ankle instability. This study aimed to evaluate the clinical outcomes of skeletally immature patients who underwent all-inside ligament repair. METHODS: Skeletally immature patients who underwent surgery for ankle instability between 2018 and 2022 were retrospectively evaluated. All patients were treated arthroscopically using an all-inside ligament repair technique, allowing an all-epiphyseal anatomical repair of the ligament remnant. Clinical outcomes were assessed pre- and postoperatively using Visual Analogue Scale (VAS), Foot Functional Index (FFI) score and Foot and Ankle Ability Measure-Sports subscale (FAAM-SS). Postoperative magnetic resonance imaging (MRI) was routinely performed at 3 months to evaluate ligament repair and detect any physeal violation. At final follow-up, patient satisfaction, complications, lower-limb axial deviations or clinical signs of physeal violation were recorded. RESULTS: Forty patients aged 8-15 years (21 females; mean age 13.8 ± 2.3 years) were included. Mean follow-up was 44.8 months ± 16.5 (range, 24-78). An anterior talofibular ligament (ATFL) tear was identified in all cases, with concomitant calcaneofibular ligament detachment observed in four patients. All clinical scores improved significantly (p < 0.001). Mean FFI and FAAM-SS scores improved from 35.6 ± 14.0 (range, 11-69) and 50.3 ± 14.0 (range, 15-78) preoperatively to 3.9 ± 6.4 (range, 0-26) and 95.4 ± 8.3 (range, 68-100) postoperatively. Mean VAS improved from 5.4 ± 2.5 (range, 1-8) to 0.4 ± 0.8 (range, 0-3). No cases of physeal violation were detected on postoperative MRI. No major complications, axial deviation or clinical signs of growth plate injury were observed. CONCLUSIONS: Ankle instability in skeletally immature patients can be successfully treated with arthroscopic all-inside ligament repair. This technique provides an all-epiphyseal anatomical repair of the ligament remnant with a low risk of physeal violation and results in excellent clinical outcomes. LEVEL OF EVIDENCE: Level IV, retrospective case series.