The Influence of Suture-Tape Augmentation on Biological Healing of the Anterior Talofibular Ligament in Chronic Ankle Instability: A Quantitative Analysis Using MRI

Abstract

While the effectiveness of suture-tape augmentation for chronic ankle instability has been supported biomechanically and clinically, little information is available regarding biological changes of the lateral ligaments postoperatively. This study aims to quantitatively evaluate ligament regeneration with MRI after suture-tape augmentation. Forty-six patients underwent MRI scan at follow-up of a minimum of 1 year after lateral ligaments augmentation using suture-tape. The signal-to-noise ratio (SNR) and width of anterior talofibular ligament (ATFL) were measured on preoperative and postoperative MRI by 3 researchers. The degree of biological healing of ATFL was analyzed based on the change of SNR and comparison with normal contralateral ankle. Clinical outcomes were evaluated with the Foot and Ankle Outcome Score, Foot and Ankle Ability Measure. Mean Foot and Ankle Outcome Score and Foot and Ankle Ability Measure scores improved significantly from 63.1 to 92.7, and 59.6 to 91.5 points at final follow-up, respectively (p < .001). Mean SNR and width of ATFL were changed insignificantly from 8.24 to 7.96, and 1.88 mm to 2.05 mm at final follow-up, respectively (p = .391, .509). As compared to contralateral side, there were significant differences in both mean SNR and width of the ATFL, respectively (p < .001, p = .0012). Spearman's correlation analysis revealed no significant association between clinical outcomes and degree of biological healing of ATFL based on MRI. Despite significant improvement in patient-reported clinical outcomes, the influence on ligament regeneration of suture-tape augmentation for chronic ankle instability was insignificant. In addition, there was no significant correlation between clinical outcomes and degree of biological healing of the ATFL.