Arthroscopy-assisted repair of latent syndesmotic instability of the ankle.

PURPOSE The purpose of this study was to investigate the results of repair of latent ankle syndesmotic instability and widening by an arthroscopic and percutaneous approach. METHODS This case study series presents 6 patients who presented with latent syndesmotic instability after sustaining a rotational ankle injury. All 6 patients underwent arthroscopy-assisted repair and percutaneous fixation of the disrupted ankle mortise. Objective radiographic findings were obtained pre- and postoperatively as well as subjective patient outcomes using American Orthopaedic Foot and Ankle Society (AOFAS) ankle-hindfoot score. RESULTS After a minimum of 2 years of follow-up, all patients had improvement of their AOFAS scores with a mean change of 32 (standard deviation, 7.0; P = .0001). The function component of the AOFAS score had the largest change from preoperative to postoperative status, with a value of 15 (P = .0009). Radiographic parameters were improved in all 6 patients. The reduction of the medial clear space was the most consistent finding, with a postoperative medial clear space ranging from 2.6 to 3.5 mm (mean change, 3.2 mm; P = .0002). CONCLUSIONS Our small series, with a minimum follow-up of 24 months, suggests that arthroscopy-assisted treatment of latent syndesmotic instability is an effective method. The primary outcome measure of AOFAS scores showed statistically significant improvement in pain and function at final follow-up. Alignment of the ankle did not exhibit statistically significant changes. Both of the secondary radiographic outcome measures were statistically improved at final follow-up. LEVEL OF EVIDENCE Level IV, therapeutic case series.