Arthroscopic Excision of a Symptomatic Os Trigonum in a Lateral Decubitus Position

Background: The purpose of this study was to introduce our technique of arthroscopic excision of the os trigonum in the lateral decubitus position through anterolateral, centrolateral, and posterolateral portals and also to investigate the safety and clinical results of this technique. Methods: Between May 2007 and May 2011, 23 ankles of 23 consecutive patients underwent subtalar arthroscopic removal of the os trigonum in a lateral decubitus position. Twenty patients were male and 3 were female. All patients injured their ankles during sports activities. Mean duration of postoperative follow-up was 18 months, and no patients were lost to follow-up. Clinical evaluations were performed using the American Orthopaedic Foot and Ankle Society (AOFAS) ankle-hindfoot score and the visual analog scale (VAS) for pain. The time to return to work and sports activities was assessed. Results: Average AOFAS ankle-hindfoot score increased from 71.3 (range, 59-85) preoperatively to 94.7 (range, 90-100) postoperatively, and VAS for pain decreased from 6.7 (range, 3-10) to 1.5 (range, 0-3). Average plantarflexion of the ankle increased from 28.8 degrees (range, 15-40) preoperatively to 42.5 degrees (range, 25-50) postoperatively. Mean time to resumption of sports activities was 6.7 weeks (range, 5-12). There were no major complications in any patient. Conclusion: Arthroscopic excision of a symptomatic os trigonum using anterolateral, centrolateral, and posterolateral portals in the lateral decubitus position was a safe and effective technique. Level of Evidence: Level IV, retrospective case series.