The present prospective study was conducted to evaluate the clinical outcomes of the new ligament reattachment procedure for chronic lateral ankle instability in high-demand athletes. A total of 24 athletes <30 years old were followed for >2 years after undergoing the modified Brostrom procedure using the suture bridge technique. The clinical evaluation included the Karlsson score, the Sefton grading system, and the period to return to exercise. As an evaluation of mechanical stability, the talar tilt angle and anterior talar translation were measured on stress radiographs. The Karlsson score had improved significantly from a preoperative average of 43.5 points to 92.2 points. Using the Sefton grading system, 22 (91.7%) patients achieved satisfactory results. The period to return to exercise was as follows: a mean of 8.4 weeks for jogging, 12.5 weeks for spurt running, 10.5 weeks for jumping, 9.2 weeks for 1 leg standing for >1 minute, 10.6 weeks for walking on uneven ground, and 11.2 weeks for going downstairs. The talar tilt angle and anterior talar translation had improved significantly from the preoperative average of 15.4° and 13.3 mm to 3.8° and 4.2 mm at 2 months postoperatively and 4.9° and 4.8 mm at the final follow-up visit, respectively. The modified Brostrom procedure using the suture bridge technique resulted in satisfactory clinical outcomes comparable to those with conventional ligament reattachment techniques. The suture bridge technique appears to be an effective treatment option for chronic ankle instability in high-demand athletes.