Arthroscopic treatment combined with the ankle stabilization procedure is effective for sinus tarsi syndrome in patients with chronic ankle instability

Purpose This study aimed to investigate the results of arthroscopic treatment combined with ankle stabilization procedure for sinus tarsi syndrome (STS) in patients with chronic ankle instability (CAI). Methods A total of 57 patients (31 males and 26 females, average age 29.9 +/- 8.4 years ranging from 15 to 52 years) with STS and CAI who accepted operation from 2013 to 2015 were included in this retrospective study. Surgical procedures included thorough tarsal sinus debridement and repair or reconstruction of lateral ankle ligaments according to the quality of ligaments. American Orthopedic Foot and Ankle Society (AOFAS) score, Karlsson score, and Tegner score were evaluated preoperatively and at final follow-up. Results All the patients accepted thorough debridement of tarsal sinus. Of these, 53 patients (93.0%) had an arch structure between the posterior subtalar joint and the middle subtalar joint. Further, 54 patients accepted lateral ankle ligament repair, and 3 patients accepted ligament reconstruction. A total of 40 patients were followed up with an average time of 30.7 months. The modified AOFAS score increased from 62.5 (27-90) to 93 (67-100), the Karlsson score increased from 57 (30-82) to 90 (55-100), and the Tegner score increased from 1 (1-3) to 5 (1-8). Conclusions Arthroscopic treatment combined with the ankle stabilization procedure could get satisfactory results for STS in patients with CAI. The arch structure composed by medial calcaneal component of the medial root of the inferior extensor retinaculum (MCC) might contribute to the pathological mechanism of STS.