Grant: Research Tools and Instruments

<p><strong>Rationale: </strong><br /> Mechanical testing of biological samples is a critical step in determining tissue response to mechanical stimuli. However, most mechanical testing systems are designed to test materials for specific constrained loading conditions, such as axial compression or tension. These do not replicate intricate physiological load exposures that occur commonly i<em>n vivo</em>, including multi-directional forces and application of forces to irregularly shaped tissues.</p> <p> Waterloo researchers have historically pushed the envelope in mechanical tissue testing to generate complex temporal and mechanical exposure data. Our next goal is to create even more physiological <em>in vitro&nbsp;</em><span style=""font-size: 12.8px; line-height: 1.5em;"">exposures that provide insight into how injuries initiate, the role of laxity or instability to injury, and the specific contributions of muscles to joint loading. Existing equipment cannot accommodate these testing conditions. Further, we aim to expand testing into novel materials and applications, including murine tendon and archaeological specimens, and forensic anthropological research.</span><em><br /> </em><br /> <strong>Equipment type and capabilities: </strong><br /> We propose the acquisition and integration of an innovative focal tissue loading system. This will include a highly repeatable, flexible robot arm and controller. Distinct advantages of the proposed system include the ability to specify any path and specific location for applied loads, and control exposures based on applied forces, the path of the end effector, and applied moment directions and magnitudes. Force measuring equipment, polarized lighting and imaging components, and an indenter suite are envisioned to complete the comprehensive tissue assessment system. The new system will be integrated with our advanced macroscopic mechanical testing system and our microscopic biaxial tissue tester, creating a unique system of enhanced capability to evaluate diverse tissue mechanics characterizations.</p> <p><span style=""font-size: 12.8px; line-height: 1.5em;"">The requested equipment will enable pursuit of vital but previously inaccessible research questions regarding how tissues respond to a wide variety of relevant and understudied exposures. Without the new equipment, understanding of the underlying mechanisms of tissue damage will remain incompletely described, complicating the ability to limit or modify exposures to prevent deleterious scenarios. The primary tissue mechanical responses characterized through use of the proposed equipment has wide ranging applications, including preventative man-machine interface designs, exposure and best practice approaches for occupational design, resolving functional morphology questions, gaining insight into skeletal muscle physiology, evaluating cartilage damage pathways, and the identification of effective tissue preservation methods.</span></p>