Effect of Modified Broström Procedure With Periosteal Flap Augmentation After Subfibular Ossicle Excision on Ankle Stability

Abstract

Background: The study evaluated the clinical and radiographic outcomes of the modified Broström procedure (MBP) with periosteal flap augmentation after large subfibular ossicle excision for chronic lateral ankle instability (CLAI). Methods: Twenty-two CLAI cases with a large ossicle (≥10 mm) were treated consecutively using the MBP with periosteal flap augmentation after ossicle excision. The mean follow-up duration was 20 months (12-33). For clinical assessment, the visual analog scale (VAS), American Orthopaedic Foot & Ankle Society (AOFAS) score, and Karlsson-Peterson score were evaluated preoperatively and at the last follow-up. For radiographic assessment, the size of the ossicle was measured by magnetic resonance imaging, and the talar tilt angle and anterior talar displacement were measured preoperatively and at the last follow-up. Results: The VAS, AOFAS, and Karlsson-Peterson scores improved from 6.3, 68.7, and 56.9 preoperatively to 1.6, 94.5, and 92.4 at the last follow-up, respectively. The mean size of the ossicles was 14.8 mm (11-21 mm). The talar tilt angle and anterior talar displacement improved from 11.2 degrees and 8.3 mm preoperatively to 4.4 degrees and 3.9 mm at the last follow-up, respectively. Conclusion: MBP combined with periosteal flap augmentation after ossicle excision provided good clinical and radiographic outcomes in CLAI with a large ossicle. Level of Evidence: Level IV, case series.