The Effects of Testing Environment on Soft Tissue Properties

Accurate characterization of the mechanical behavior of soft tissues is needed for medical simulation, diagnostic, and tissue engineering purposes. Determining the complex behavior of soft tissues requires mechanical testing in their natural state. Such in vivo tests are wrought with ethical, accessibility, physiological noise, and uncontrolled boundary condition issues. Several groups have developed means for in vivo mechanical testing, but the interpretation of their results remains to be understood. Conversely, testing biological tissues under ex vivo conditions is desirable because it allows for precise control of the boundary conditions, ease of accessibility, and use of fewer animals. However, the behavior and properties of the tissues are drastically altered once removed from their natural state. This study seeks to quantify the differences in the viscoelastic response of soft tissues between four different test conditions. We introduce a new ex vivo set-up that allows for near in vivo testing.