Articular cartilage is a remarkable material. Lining the ends of long bones, it provides decades of pain free ambulation, a consequence of complex, poroviscoelastic material behavior. However, when cartilage is structurally damaged, osteoarthritis can occur, negatively impacting overall quality of life by reducing mobility. This is in part due to the sparse cell population and low metabolic activity in cartilage, which leads to relatively little native repair in cartilage. Developing effective preventive and reparative strategies for osteoarthritis requires a deeper understanding of both failure behavior and mechanobiology. This talk will cover our recent research in both of these areas, starting with failure behavior. Using a microindentation experimental set-up, we induced cartilage fracture across a range of loading rates with altered matrix integrity. This provided insight into the role of poroviscoelastic relaxations in cartilage failure, and allowed us to identify a pre-relaxed regime from which we estimated fracture toughness. To evaluate cartilage mechanobiology, we adapted a technique to evaluate relative glycolysis and oxidative phosphorylation activity over time. Our results are the first to evaluate the immediate pathway-specific metabolic mechanobiological response of cartilage, providing insight into the different responses to physiological versus injurious loading. Together, these basic science studies lay foundations for leveraging mechanics to reduce the burden of osteoarthritis.
Corinne Henak is an assistant professor in the Department of Mechanical Engineering at the University of Wisconsin-Madison, with affiliate appointments in the Departments of Biomedical Engineering and Orthopedics and Rehabilitation. She graduated with a bachelor’s degree in Mechanical Engineering from the University of Denver in 2008, and a PhD in Bioengineering from the University of Utah in 2013 working with Prof. Jeffrey Weiss. Dr. Henak trained as a post-doc in Biomedical Engineering at Cornell University working with Profs. Larry Bonassar and Itai Cohen from 2013-2015. Research in the Henak Lab focuses on mechanically-mediated diseases, with an emphasis on microscale mechanics to predict mechanical and biological tissue responses.
Host: Professor Mariana Kersh