Biomechanical Comparisons of Anterior Cruciate Ligament Avulsion Fracture Fixation Using High-Strength Suture and Ultra-High Molecular Weight Polyethylene Suture Tape in a Porcine Model.

A wide variety of fixation methods have been reported to fix anterior cruciate ligament (ACL) tibial avulsion fractures, but there have been no studies into the fixation of these fractures with ultra-high molecular weight polyethylene (UHMWPE) suture tape as an alternative to conventional thread. Type III ACL tibial avulsion fractures were created in 20 skeletally immature porcine knees. All specimens were randomized into two treatment groups: (1) pullout repair using no. 2 suture fixation and (2) pullout repair using UHMWPE suture tape fixation. The specimens were tested cyclically (20 cycles, 0-40 N, 100 mm/min) in the direction of the native ACL and loaded to failure (100 mm/min) on a tensile tester. Statistically significant differences between the structural properties (displacement, upper yield load, maximum load, linear stiffness, and elongation at failure) under cyclic loading and single-cycle loading were analyzed. Displacement during cyclic testing was 1.56 ± 1.03 mm in the UltraBraid group and 0.99 ± 0.48 mm in the SUTURETAPE group, with no significant differences found between the groups (p = 0.13). There were no significant differences in upper yield load (161.9 ± 68.9 N in the UltraBraid group, 210.4 ± 60.1 N in the SUTURETAPE group, p = 0.11), linear stiffness (14.7 ± 4.7N/mm in the UltraBraid group, 18.1 ± 7.9 N/mm in the SUTURETAPE group, p = 0.27), or elongation at failure (20.1 ± 8.0 mm in the UltraBraid group, 21.5 ± 7.2 mm in the SUTURETAPE group, p = 0.69). On the other hand, significant differences were observed in maximum load in the SUTURETAPE group (219.7 ± 89.2 N in the UltraBraid group, 319.3 ± 92.6 N in the SUTURETAPE group, p = 0.025).