Presoaking of Semitendinosus Graft With Vancomycin Does Not Alter Its Biomechanical Properties: A Biomechanical In Vitro-Controlled Study Using Graft From Living Donors

Abstract

Purpose: To compare the biomechanical properties of human semitendinosus graft presoaked with or without vancomycin under a load to failure tensile test.

Methods: Thirty semitendinosus grafts harvested during anterior cruciate ligament reconstruction were included. These were dissected equally into 2 halves and subsequently randomly allocated to a vancomycin group and to a control group. A digital caliper was used to precisely measure each samples thickness, length, and width. For the vancomycin group, samples were presoaked in a solution of 5 mg/mL vancomycin for a duration of 10 minutes and the control group samples were presoaked in a physiological serum equally for 10 minutes. Mechanical testing was performed on a universal testing machine (Instron 5566-A) after a preconditioning of 10 cycles of 1 mm extension and a progression of 10 mm/min to failure for each sample. The stress-strain curve was obtained to determine the elastic modulus (Young's modulus), the ultimate tensile stress, the ultimate tensile elongation (UTE) before failure and the elasticity limit.

Results: For the control group, the average Young's modulus value was 4.8 ± 0.8, the average UTS was 25.2 ± 5.2 MPa, the average percentage of UTE was 78 ± 17%, and the average elasticity limit value was 17.3 ± 5.3 MPa. For the vancomycin group, the average Young's modulus value was 4.7 ± 0.9, the average ultimate tensile stress was 24.1 ± 6.1 MPa, the average percentage of UTE was 82 ± 14%, and the average elasticity limit value was 18.5 ± 5.9 MPa. No significant difference was observed between the 2 groups for all investigated parameters.

Conclusions: Presoaking of human semitendinosus graft with vancomycin does not alter its biomechanical properties.

Clinical relevance: This study demonstrates that vancomycin presoaking used to prevent post-anterior cruciate ligament reconstruction septic arthritis does not affect immediate biomechanical properties of semitendinosus tendons.