Elder, Steven H.
Kent-First, Marijo G.
Butler, R. Allen
Date of Degree
Graduate Thesis - Open Access
Agricultural and Biological Engineering
Master of Science
James Worth Bagley College of Engineering
Department of Agricultural and Biological Engineering
The ACL is one of the major ligaments in the knee connecting the femur to the tibia which provides stability by resisting shear in sagittal plane. ACL tears occur in 1 out of 3000, and due to inability to heal, reconstructive surgeries are performed at a rate of 200,000/year. Final graft fixation tension during surgery has been shown to wane due to stress-relaxation which has been correlated with negative clinical outcomes. Therefore, preconditioning, which currently is an isometric load (88N), is performed to remove stress-relaxation after the final tension has been applied in vivo. Three preconditioning protocols, creep, stress relaxation, and none, were tested to show significant differences and variance in graft tension after 30 minutes. The results suggest that the current preconditioning protocol may not be efficient enough to remove stress-relaxation after final fixation, and that a creep protocol causes less variability than the other preconditions performed.
Crawford, Richard Lee, "Protocols For Preconditioning Of Patellar Tendon For Anterior Cruciate Ligament Reconstruction" (2008). Theses and Dissertations MSU. 3673.