The Biomechanical Stability of Bone Staples in Cortical Fixation of Tendon Grafts for Medial Collateral Ligament Reconstruction Depends on the Implant Design

Abstract

Background: The promising biomechanical stability of bone staples (BSs) in cortical fixation of tendon grafts for medial collateral ligament (MCL) reconstruction has been revealed by a previous investigation. However, it is currently unknown if the biomechanical stability of cortical fixation of tendon grafts depends on the BS design. Purpose: To assess the biomechanical stability of cortical fixation of tendon grafts in knee surgery using 4 different BS designs. Study Design: Controlled laboratory study. Methods: Cortical fixation of tendon grafts was performed in a porcine knee model at the tibial insertion area of the MCL using 4 different BS designs (n = 40): 8-mm width without spikes (n = 10), 8-mm width with spikes (n = 10), 14-mm width with spikes (n = 10), and 13 mm–wide 4-prong staples with spikes (n = 10). Specimens were mounted in a materials testing machine, and cyclic loading was applied to the tendon graft (500 cycles at 50 and 100 N, respectively), followed by load-to-failure testing. The Kruskal-Wallis test was performed for statistical analysis (P