Biomechanical Outcomes After Bioenhanced Anterior Cruciate Ligament Repair and Anterior Cruciate Ligament Reconstruction Are Equal in a Porcine Model

Purpose: The objective of this study was to compare the biomechanical outcomes of a new method of anterior cruciate ligament (ACL) treatment, bioenhanced ACL repair, with ACL reconstruction in a large animal model. Methods: Twenty-four skeletally immature pigs underwent unilateral ACL transection and were randomly allocated to receive bioenhanced ACL repair with a collagen-platelet composite, allograft (bone-patellar tendon-bone) reconstruction, or no further treatment (n = 8 for each group). The structural properties and anteroposterior laxity of the experimental and contralateral ACL-intact knees were measured 15 weeks postoperatively. All dependent variables were normalized to those of the contralateral knee and compared by use of generalized linear mixed models. Results: After 15 weeks, bioenhanced ACL repair and ACL reconstruction produced superior biomechanical outcomes to ACL transection. However, there were no significant differences between bioenhanced ACL repair and ACL reconstruction for maximum load (P = .4745), maximum displacement (P = .4217), or linear stiffness (P = .6327). There were no significant differences between the 2 surgical techniques in anteroposterior laxity at 30 degrees (P = .7947), 60 degrees (P = .6270), or 90 degrees (P = .9008). Conclusions: Bioenhanced ACL repair produced biomechanical results that were not different from ACL reconstruction in a skeletally immature, large animal model, although the variability associated with both procedures was large. Both procedures produced significantly improved results over ACL transection, showing that both were effective treatments in this model. Clinical Relevance: Bioenhanced ACL repair may one day provide an alternative treatment option for ACL injury.