Summary

ose of this study was to determine the course and safe distances achieved with our modified coaxial portals for ankle arthroscopy and to report the clinical results.

Abstract

Purpose

The purpose of this study was to determine the course and safe distances achieved with our modified coaxial portals for ankle arthroscopy and to report the clinical results. Methods: Thirty embalmed cadaveric and ten fresh-frozen ankle specimens were used for anatomic measurements and trial operations. The posteromedial portal via the posterior tibial tendon sheath was first established. The posterolateral portal was subsequently created immediately behind the posterior border of the lateral malleolus and anterior to the peroneal tendons using an inside-out technique. The coaxial portals were finally finished with cannulas left in place. A clinical study was conducted with posterior ankle arthroscopy performed on 18 ankles in 15 patients. All patients were evaluated for any complications with an average follow-up of 38 months. Results: The posterior tibial nerve, posterior tibial artery and peroneal artery were located at a mean distance of 8.7mm, 10.1mm and 12.9mm respectively from the near edge of the kirschner wire used as a reference to the coaxial portals. The sural nerve and lesser saphenous vein were at a larger distances of 27.6 mm and 28.3 mm, respectively. The mean West Point Score at the time of the latest follow-up was 91.5 points (range, 76-100). There were 9 excellent results, 3 good results and 1 fair result. No patient showed any complication related to the modified coaxial portals. Conclusions: The modified coaxial portals appeared to have a safe distance from the neurovascular structures in our anatomic study. Clinically, this technique is safe, effective, and reproducible.