Biomechanical properties of reinforced bone-anterior cruciate ligament-bone allografts for anterior cruciate ligament reconstruction in rabbits

Objective: The objective of present study was to investigate the initial biomechanical properties of a reinforced bone-anterior cruciate ligament-bone (RB-ACL-B) allograft in the reconstruction of the ACL. Method: Seventy-five mature New Zealand rabbits were used in this study. Thirty rabbits were used to prepare the B-ACL-B allograft, while the remaining rabbits were randomly divided into three groups (n = 15): the first group underwent ACL reconstruction with the B-ACL-B allograft (B-ACL-B group); the second group, with a 4-stranded semitendinosus tendon (ST) autograft (ST group); and the final group with a 2-stranded ST-reinforced B-ACL-B allograft (RB-ACL-B group). The non-operated contralateral leg served as the normal control (NC group). The biomechanical properties of the repair were tested in five rabbits from each group on 16, 32 and 48 weeks, postoperatively, to assess the efficacy of the RB-ACL-B allograft in ACL reconstruction. Result: The mean maximum force for the RB-ACL-B allograft was 41%, 58%, and 68% of NC group (P < 0.05) at 16, 32, and 48 weeks, respectively. Compared with mean maximum forces of 31%, 45%, and 55% for the ST group (P < 0.05) and 23%, 34%, and 38% for the B-ACL-B group (P < 0.05). Although the biomechanical properties of the experimental groups failed to reach the level of the NC group, the biomechanical properties of the RB-ACLB group were better than those of the ST and B-ACL-B groups. Conclusion: The RB-ACL-B allograft has good biomechanical properties and offers superior outcomes over the ST and B-ACL-B grafts in ACL repair. The RB-ACL-B allograft may offer an effective solution for ACL reconstruction.