A tear of the anterior cruciate ligament in a knee isn't just painful in the moment—the injury also increases a patient's risk of developing osteoarthritis later.
At the University of Delaware, a research team led by Tom Buchanan, the George W. Laird Professor of Mechanical Engineering and Director of the Delaware Rehabilitation Institute, is teasing out what exactly happens to cartilage as a result of anterior cruciate ligament (ACL) injuries. The team hopes that this insight can be utilized in the development of improved osteoarthritis prevention strategies.
The team uses magnetic resonance imaging (MRI) test results, finite element models, gait analysis and biochemical analysis to study ACL injuries and determine which stresses on cartilage may be indicative of osteoarthritis. To complete this research, they utilize facilities at the UD's Center for Biomedical and Brain Imaging as well as UD's Science, Technology and Advanced Research (STAR) Campus. At STAR, the team collaborates with UD's top-ranked Department of Physical Therapy to collect data from patients and understand the clinical aspects of the injuries they study. "Based on what we identify, maybe physical therapists could treat patients differently," said Buchanan.
The results of one recent paper, published in the Journal of Orthopaedic Research, were surprising. The team studied knee gait variables, muscle co-contraction and knee joint loading in young people with a history of ACL trouble. They found that high muscle co-contraction does not always result in high knee joint loading, thought to be associated with arthritis.
"This suggests that arthritis isn't just caused by really high forces, but can also be caused by too low forces on the joint," said Buchanan. The ideal range of forces may in fact be a very narrow window.
Laura Sturgill, a biomedical engineering undergraduate in the class of 2019, joined Buchanan's lab as a research assistant in 2018 because she wanted more experience studying the mechanical aspects of biomedical engineering. "These applications of statics and dynamics are especially interesting," she said.
Kelsey Neal and Jack Williams, doctoral students in mechanical engineering, use motion capture and MRI to assess the effects of ACL tears. Neal chose to study in Buchanan's lab because she wanted to work on rehabilitation engineering and was impressed by the unique setup that allows her to work so closely with clinicians. "We can see how we are affecting patients' lives," she said.
Neal was also drawn to UD because of the Perry Initiative, a nonprofit organization co-founded by associate professor Jenni Buckley to inspire young women to be leaders in orthopedic surgery and engineering. As a program specialist for the organization, Neal runs programs across the country to introduce high school girls to surgical techniques that were pioneered by engineers. Buchanan is a member at large of the organization's board of directors.
Buchanan is also the program coordinator for Delaware's Center for Translational Research ACCEL Program to support and expand clinical and translational research in the state. In October 2018, officials announced that UD and four other institutions will receive $25 million over five years from the National Institutes of Health and the state of Delaware to continue these research programs for improved patient care and public health.
"Engineers play an important role in the expansion of health-related research at UD and beyond," said Buchanan.