Upcoming Event

Johnson & Johnson Mechanical Testing and Analysis Summit 
Robb Colbrunn, Ph.D., Guest Speaker
Director of BioRobotics and Mechanical Testing Core
Medical Device Solutions (MDS) Cleveland Clinic
Adjunct Assistant Professor, Cleveland Clinic Lerner College of Medicine of Case Western Reserve University
September 18-20, 2018
Syracuse, IN

"Back to Metabolism Basics:Transport and Bioenergetics in Tumors and Brain Endothelial Cells"
Lester R. Drewes, Ph.D.
Professor of 
Biochemistry & Molecular Biology
Director, Graduate Programs, MSD
Department of Biomedical Sciences
University of Minnesota Medical School Duluth
Hosted by Chaitali Ghosh, PhD.
September 28, 2018

Role of the Native Fiber Bundles of the Anterior Cruciate Ligament in Knee Joint Kinematics

Client: Joe Carney M.D. / US Navy

Services Provided: Experiment Design / Robotic Knee Joint Testing / Data Analysis / Manuscript Preparation

Anatomical descriptions of the Anterior Cruciate Ligament (ACL) typically describe two distinct fiber bundles, the anterior-medial bundle (AMB) and the posterior-lateral bundle (PLB). This has inspired the development of double-bundle (DB), four-tunnel, reconstruction techniques for ACL ruptures. There are, however, no clinical studies yet that show an advantage of one technique over the other. Recent biomechanical studies have shown that the DB technique has the potential to reduce knee joint laxity, but it is not yet clear to what extent this is desirable or replicates the function of the native ACL bundles. The aim of this study was to determine the role of the native AMB and PLB via robotic testing in a cadaver model with and without weightbearing. Our results show that the AMB has a larger effect on anterior tibia translation than the PLB. Both bundles, however, appear to contribute equally to rotational stability at 15 degrees flexion or more. The PLB tended to have a larger contribution to rotational stability but only at full extension. It is premature to interpret these results with respect to the debate on single vs. double bundle reconstruction, but our results suggest that a single bundle reconstruction, placed at the AMB insertions, may be sufficient to restore translational stability. It should be kept in mind that these results were obtained without compressive load on the joint. Preliminary results suggest the ACL bundles have less influence on passive knee joint motion when Lachman and pivot shift tests are performed during simulated weightbearing.