Biomechanical Comparison Between Bashti Bone Plug Technique and Biodegradable Screw for Fixation of Grafts in Ligament surgery

Abstract

<br/><span style="font-size: xx-small;">Background: </span><span style="font-family: Arial,Arial; font-size: xx-small;"><span style="font-family: Arial,Arial; font-size: xx-small;">Ligament reconstruction is a common procedure in orthopedic surgery. Although several popular </span></span><span style="font-family: Arial,Arial; font-size: xx-small;"><span style="font-family: Arial,Arial; font-size: xx-small;">techniques are currently in use, new methods are proposed for secure fixation of the tendon graft into the bone tunnel. </span></span><br/><span style="font-size: xx-small;">Purposes: </span><span style="font-family: Arial,Arial; font-size: xx-small;"><span style="font-family: Arial,Arial; font-size: xx-small;">We sought to introduce our new technique of Bashti bone plug for fixation of soft tissue graft in anterior cruciate ligament (ACL) reconstruction and to compare its biomechanical features with conventional absorbable interference screw technique in a bovine model. </span></span><br/><span style="font-size: xx-small;">Methods: </span><span style="font-family: Arial,Arial; font-size: xx-small;"><span style="font-family: Arial,Arial; font-size: xx-small;">Twenty pairs of bovine knees were harvested after death. Soft tissue was removed and the Achilles tendon was harvested to be used as an ACL graft. It was secured into the bone tunnel on the tibial side via two different </span></span><span style="font-family: Arial,Arial; font-size: xx-small;"><span style="font-family: Arial,Arial; font-size: xx-small;">methods: Bashti Bone Plug technique and conventional screw method. Biomechanical strength was measured using 200 N and 300 N cyclic loading on the graft. Pull out strength was also tested until the graft fails. </span></span><br/><span style="font-size: xx-small;">Results: </span><span style="font-family: Arial,Arial; font-size: xx-small;"><span style="font-family: Arial,Arial; font-size: xx-small;">No graft failure was observed after 200 N and 300 N cyclic loading in either fixation methods. When testing for pull out failure, 21 tendons (53%) were torn and 19 tendons (48%) slipped out. No fixation failure occurred, which did not reveal a significant difference between the bone plug or interference screw group (</span></span><em><span style="font-family: Arial,Arial; font-size: xx-small;"><span style="font-family: Arial,Arial; font-size: xx-small;">P</span></span></em><span style="font-family: Arial,Arial; font-size: xx-small;"><span style="font-family: Arial,Arial; font-size: xx-small;">=0.11). The mean pull out </span></span><span style="font-family: Arial,Arial; font-size: xx-small;"><span style="font-family: Arial,Arial; font-size: xx-small;">force until failure of the graft was 496±66 N in the screw group and 503±67 N in the bone plug group (</span></span><em><span style="font-family: Arial,Arial; font-size: xx-small;"><span style="font-family: Arial,Arial; font-size: xx-small;">P</span></span></em><span style="font-family: Arial,Arial; font-size: xx-small;"><span style="font-family: Arial,Arial; font-size: xx-small;">=0.76). </span></span><br/><span style="font-size: xx-small;">Conclusions: </span><span style="font-family: Arial,Arial; font-size: xx-small;"><span style="font-family: Arial,Arial; font-size: xx-small;">Our suggested fixation technique of Bashti bone plug is a native, cheap, and feasible method that provides comparable biomechanical strength with interference screw when soft tissue fixation was attempted in bovine </span></span><span style="font-family: Arial,Arial; font-size: xx-small;"><span style="font-family: Arial,Arial; font-size: xx-small;">model. </span></span>