Comparison of Midterm Outcomes between All-Inside Arthroscopic and Open Modified Broström Procedures as Treatment for Chronic Ankle Instability.

Background: Although the all-inside arthroscopic modified Broström operation (AMBO) and open modified Broström operation (OMBO) for chronic lateral ankle instability (CLAI) showed favorable outcomes up to 1-year short-term follow-up, concerns about the long-term stability of AMBO are still present. Therefore, we aimed to compare midterm outcomes between the 2 methods by extending the observation period. Methods: Fifty-four patients undergoing ankle surgery between August 2013 and July 2017 were included in the AMBO (n = 37) and OMBO (n = 17) groups. The American Orthopaedic Foot and Ankle Society (AOFAS) ankle-hindfoot scale and a visual analog scale (VAS) were used to evaluate the clinical outcomes. Anterior drawer test and talar tilt angle were used to evaluate the radiological outcomes. The mean follow-up duration was 59.69 months. Results: The 2 groups both showed improved clinical and radiological results statistically. In addition, they did not differ in age, sex, or preoperative AOFAS ankle-hindfoot scale score, VAS score, anterior drawer test, or talar tilt angle. No significant difference in the final follow-up postoperative clinical scores or radiological outcomes was observed. Conclusions: AMBO and OMBO as treatments for CLAI did not yield differing clinical or radiological outcomes at a mean follow-up time point of 59.69 months.