Subtalar arthroscopy for sinus Tarsi syndrome: arthroscopic findings and clinical outcomes of 33 consecutive cases.

PURPOSE The purposes of this study were to identify the pathologic findings of sinus tarsi syndrome (STS) by subtalar arthroscopy and to evaluate the results of arthroscopic treatments in 33 consecutive cases. METHODS A retrospective review was performed in 31 consecutive patients (33 cases) who underwent subtalar arthroscopic treatment for STS. The mean follow-up duration was 24 months (range, 18 to 36 months). Patients were evaluated by use of arthroscopic findings (recorded on videotapes and photographs) and clinical outcomes, which included visual analog scale and American Orthopaedic Foot and Ankle Society ankle-hindfoot scores. RESULTS Arthroscopic findings showed partial tear of the interosseous talocalcaneal ligament in 29 cases (88%), synovitis in 18 (55%), partial tear of the cervical ligament in 11 (33%), arthrofibrosis in 8 (24%), and soft-tissue impingement in 7 (21%). The mean visual analog scale score improved from 7.3 points (range, 6 to 9 points) preoperatively to 2.7 points (range, 1 to 4 points) postoperatively (P < .005), and the mean American Orthopaedic Foot and Ankle Society ankle-hindfoot score improved from 43.1 points (range, 21 to 65 points) preoperatively to 86.2 points (range, 72 to 100 points) postoperatively (P < .005). Of the cases, 16 (48%) had an excellent result, 13 (39%) had a good result, and 4 (12%) had a fair result. CONCLUSIONS Subtalar arthroscopy identified pathologies in the subtalar joint in patients with STS and showed that treatment of these pathologies led to improved function. LEVEL OF EVIDENCE Level IV, therapeutic case series.