A new minimally invasive method for anatomic reconstruction of the lateral ankle ligaments with a Tightrope system

Abstract

Background: Several minimally invasive anatomic reconstruction techniques of the lateral ligaments have been introduced for the treatment of chronic lateral ankle instability. However, these strategies may not always follow accurate ligament anatomic attachments, especially in the construction of the fibular bone tunnels. Objectives: This study reported a new percutaneous technique for reconstruction of the ligaments of lateral ankle anatomically with a Tightrope system. Methods: From April 2016 to August 2016, 25 ankles of 24 patients with chronic ankle instability underwent our new percutaneous anatomic reconstruction of the lateral ligaments with a Tightrope system. The operation was performed through several small incisions. The fibular tunnel was made obliquely from the anteromedial side of lateral malleolus tip towards retro-malleolar cortex. The graft was fixed in the tunnel with the help of a Tightrope system. The calcaneal tunnel and talar tunnel were made as our previous method. The mean final follow-up was 12.2 months (range 10–14). Visual Analogue Scale for pain, American Orthopaedic Foot and Ankle Society score, and patients’ subjective satisfaction were used to measure clinical outcomes. Preoperative and postoperative stress tests were performed and radiographic parameters were measured. Results: The Visual Analogue Scale decreased from 3.0 ± 1.4 to 1.3 ± 0.8 at the last follow-up (p < 0.01). The American Orthopaedic Foot and Ankle Society score was improved from 70.2 ± 5.4 preoperatively to 92.4 ± 5.3 at the final follow-up (p < 0.01). Radiologically, the mean anterior talar displacement was 13.1 ± 2.7 mm preoperatively versus 5.6 ± 1.3 mm at last follow-up (p < 0.01),and the mean varus talar tilt angle was 15.0° ± 2.4° preoperatively versus 5.6° ± 1.9° at the last follow-up (p < 0.01). Patients were satisfied (‘excellent’ or ‘good’) in 23 ankles (92%). Two patients reported residual instability but less apprehension than the preoperative condition. Conclusions: Percutaneous anatomic reconstruction of the lateral ligaments of the ankle with a Tightrope system is an anatomic and effective procedure for the treatment of chronic lateral ankle instability.