Stable Syndesmosis after Conservative and Operative Treatment of Isolated Grade II-III High Ankle Sprains with More Than Two Years Follow-up; A Retrospective Analysis with Bilateral External Torque CT

Research Type: Level 3 - Retrospective cohort study, Case-control study, Meta-analysis of Level 3 studies Introduction/Purpose: So far, there is no consent regarding the treatment of latent unstable isolated syndesmotic injuries. The aim of this study was to retrospectively analyze patients with isolated Grade II-(III) syndesmotic lesions according to syndesmotic stability, structural changes and clinical outcome. Methods: We retrospectively analyzed 10 patients with conservative and 10 patients with operative treated isolated syndesmotic lesions with a minimum of 2 years follow-up. Syndesmotic stability was assessed by bilateral external torque CT, structural changes of ligament healing by MRI and clinical outcome by clinical examination and foot specific PROM’s. Results: The scarred syndesmosis was stable in external rotation with non-significant increasing of anterior distance (AD) of 0.4mm+/-1.2, (p=0.718), posterior distance (PD) of -0.1mm+/-1.3 (p=0.709), external rotation (ED) of 1.8°+/- 2.9 (p=0.684) and tibiofibular clear space (TCS) of 0.3mm+/-0.8 (p=0.321) compared to the healthy contralateral side. There were no differences between conservative and operative treatment according to syndesmotic stability, structural changes and clinical outcome. Conclusion: There were no differences according to syndesmotic stability, structural changes and clinical outcome of conservative or operative treated isolated Grade II-III syndesmotic lesions. Sufficient healing of torn syndesmosis ligaments is essential to prevent early ankle ostearthritis, which was achieved without distinction trough both conservative and surgical treatment.