An Open Label, Multi-center, Controlled, Retrospective Study of a Biodegradable Synthetic Graft for Soft Tissue Reconstruction in Patients Suffering from Chronic Lateral Ankle Instability

Abstract

Category: Ankle; Sports Introduction/Purpose: Ankle sprains represent one of the most common injuries among both athletes and the general public (1). While most sprains resolve with conservative therapy, failure resulting in ligament laxity may necessitate surgical intervention due to pain and instability from injury to the anterior talofibular ligament (ATFL), the weakest ligament in the lateral ligamentous complex (2). Surgical repair of ATFL has relatively high success rates, however post-procedure chronic instability and pain remain a clinical challenge, with re-operation rates reported as high as 14% (3). The Artelon® FlexBand® matrix is a biocompatible, synthetic matrix designed to reinforce soft tissue repair during tendon/ligament reconstructive procedures. The goal of this study is to compare the outcomes of ATFL reconstructive surgery with and without this synthetic graft augmentation. Methods: This multi-center, IRB approved study used a combination of retrospective medical chart review and prospective procedure satisfaction phone surveys in patients that had undergone ATFL repair (isolated and non-isolated) with or without synthetic graft augmentation. These results represent an interim data analysis of an ongoing clinical study. A total of 234 patients, (82 Control and 152 FlexBand augmented) diagnosed with chronic lateral ankle instability that had failed conservative therapy, and required surgical intervention to repair the lateral ligament complex were enrolled across four different research centers. Patient demographics, physician assessment of healing progression, safety, complications necessitating a return to OR, and post-op rehabilitation schedule were analyzed. Two study sites used Visual Analog Scale (VAS) to assess pain pre-surgically and at 2, 6, and 12 week follow-up visits. Phone survey questionnaires were given to patients that reached at least 1yr post-op to assess long-term patient satisfaction and function. Results: Average patient age was 42yrs in both groups and average follow-up time was 19.2mo (FlexBand) and 28.4mo (Control). There was no statistical difference in baseline VAS pain scores between groups. Augmented patients demonstrated significantly lower VAS scores at 2-,6-, and 12-week follow-up visits (p < 0.001, p< 0.0001and p< 0.0001, respectively) compared to controls (Fig 1). In addition, a significant acceleration in return to FWB status in augmented group compared to control patients was observed (9.04 ± 0.38wks, N=101 vs. 11.82 ± 1.67wks, N=45; p = 0.027). Both groups demonstrated equivalent AE safety profiles and complications were similar across groups with 3.7% (3/82) of control and 3.9% (6/152) augmented patients requiring a return to OR, however, no AEs or complication events were related to the Flexband Device. Conclusion: Our data shows a significant reduction in VAS pain scores in patients who underwent the modified Brostrom procedure with augmentation at all follow up time points. In addition, synthetic graft augmentation may lead to earlier return to function due to the significantly lower time to achieve FWB status. Further investigation on the potential clinical benefits of ATFL augmentation with Artelon Flexband is ongoing through a prospective, randomized, controlled study. Overall, long-term (>1yr) patient satisfaction was equivalent across groups and a trend toward potential earlier recovery times were better for the augmented group than the control group.