Objectives <p>Although there are different ways, the choice of treatment for grade-I–II anterior talofibular ligament (ATFL) injuries caused by acute ankle sprain is still controversial. The primary purpose of our study was to compare the efficacies of modified Broström-Gould surgery and conservative treatment in grade-I–II ATFL injuries caused by acute ankle sprain. The secondary goal was to assess the plantar pressure characteristics of ankle sprain.</p> Methods <p>Between Sep 2022 and December 2023, 63 patients diagnosed with acute ankle sprain (ATFL grade I-II injuries) were prospectively included in the arthroscopic modified Broström-Gould surgery group (<i>n</i> = 33) and conservative treatment group (<i>n</i> = 30). The main outcomes were the ankle functional rating scale, plantar pressure and gait parameters at preoperative, and 1, 3, 6, 12, 24months postoperative. One-way repeated measures analysis of variance ( ANOVA ) and Mann-Whitney U test were used to analyze the differences at different time points after treatment.</p> Results <p>There were significant differences in gait parameters between the surgical and conservative groups at one and three months post-treatment. Additionally, the American Orthopaedic Foot and Ankle Society (AOFAS) score, Maryland Foot Score, and Visual Analogue Scale (VAS) scores were significantly different between the surgical and conservative groups after 24 months of treatment (<i>P</i> &lt; 0.001). Furthermore, at 24 months post-treatment, there were significant differences between the injured and normal groups in terms of foot contact area, foot load ratio, single and double support phases, and center of gravity shift (<i>P</i> &lt; 0.001).</p> Conclusion <p>Surgical and conservative treatments may not fully restore ankle stability and gait in patients, yet the modified Broström-Gould procedure holds the potential to restore ankle function three months sooner.</p>