Analysis of the Biomechanical Behavior of an Animal Model of Triple Hamstring Graft Configuration for Combined ACL and ALL Reconstruction with a Single Femoral Tunnel and a Single Strand for ALL Reconstruction

Abstract

Objective

To describe and biomechanically test a configuration, in an animal model that simulates the triple hamstring graft for combined anterior cruciate ligament (ACL) and anterolateral ligament (ALL) reconstruction, with a single femoral tunnel and a single strand for ALL reconstruction.

Methods

Deep flexor porcine tendons were used as the graft and fixed with titanium interference screws in a polyurethane block. The samples were divided into 3 groups: group 1 (control) – with a quadruple graft; group 2–with a simple triple graft; and group 3–with a braided triple graft. The tests were conducted using an EMIC DL 10000 (Instron Brasil Equipamentos Científicos Ltda., São José dos Pinhais, PR, Brazil) electromechanical universal testing machine.

Results

The samples in groups 1, 2, and 3 obtained mean peak forces of 816.28 ± 78.78 N, 506.95 ± 151.30 N, and 723.16 ± 316.15 N, respectively. In Group 3, braiding increased graft diameter by 9% to 14%, and caused a shortening of 4% to 8% compared with group 1, with an average peak force increase of ~ 200 N (p < 0.05). Regarding peak forces, there was no statistically significant difference between groups 1 and 3, indicating that quadruple and braided triple grafts showed similar strength results.

Conclusion

The triple-braided hamstring graft configuration for combined ACL and ALL reconstruction with a single femoral tunnel and a single strand for ALL reconstruction may become a biomechanically viable solution, with potential clinical application.

Keywords
anterior cruciate ligament; anterior cruciate ligament reconstruction; knee joint; ligaments, articular