The Use of Suture Augmentation for Graft Protection in ACL Reconstruction: A Biomechanical Study in Porcine Knees

Purpose: To biomechanically evaluate the use of the suture augmentation construct at time 0 of ACL reconstruction. Methods: Eighty porcine knees underwent ACL reconstruction using 2 techniques for graft fixation: a single suspensory construct (SSC), performed with a femoral button and tibial interference screw; and a double suspensory construct (DSC), with a femoral and tibial button. Each fixation technique was performed on 40 porcine knees divided into 4 subgroups. The first group had a nonaugmented ACL reconstruction, the second group had an ACL reconstruction with suture augmentation, and the third and fourth groups were the same as the first and second groups, with the graft resected 80% to simulate graft weakening. Ultimate load, yield load, stiffness, cyclic displacement values, and mode of failure were recorded for each graft. Results: In a weakened graft model with 80% graft resection, there was a significant increase in ultimate strength (P < .001), yield strength (P < .001), and cyclic displacement (P < .001) with suture augmentation. There was no significant increase in stiffness with suture augmentation with either construct (P = .278). In the setting of an intact graft, there were no differences in either SSC or DCS groups with or without suture augmentation. Conclusions: The addition of a suture to ACL reconstruction techniques resulted in minimal changes in baseline biomechanical characteristics while improving ultimate load, yield load, and cyclic displacement in a weakened graft model. Clinical Relevance: Suture augmentation of ACL reconstruction may confer improved integrity of the graft and is worth consideration and future clinical study.