Combining Displacement Field and Grip Force Information to Determine Mechanical Properties of Planar Tissue With Complicated Geometry

摘要: Soft-tissue characterization using planar biaxial testing and nominal stress–strain curves usually relies on certain conditions1: The sample should have a shape, (e.g., square or cruciform) that tends to produce homogeneous strain fields in the central region. If is fibrous, fiber orientation be known aligned with axes of test system. Strain measured far from any rigid boundary, such as grip attachment bone. These criteria are often met Refs. [3–9]), but for some tissue types, meeting one more impossible. The may, example, too small allow isolation large enough shaped create region center. Aligning material does not generate shear [10]. Furthermore, if improperly aligned, variation response will increase, which could hinder elucidation complex behaviors coupling between two directions Other groups [e.g., Ref. 10] used good effect off-axis fibrous samples. This only effective, however, when known. When unknown and/or objective determine orientation, current study, force-stretch data alone insufficient. It also may undesirable even impossible remove bone, restricts one's ability align direction apparatus leads inhomogeneity field. An example these challenges found AF intervertebral disk, particularly seeks do single lamella experiments. Although experiments been performed uniaxial [11–13] modes [14–16], intact bone [12–14,16] attractive both because direct relevance vivo loading minimized damage. Figure ​Figure11 shows attached axial vertebral bone. geometry conducive field, principal apparatus. Fig. 1 Lamella AF. labeled, anisotropic fibers 30 deg horizontal axis, along dotted line. dissected removed cut ... Sample geometries inhomogeneous pose considerable challenge investigator, advent image-correlation-based methods tracking motion over entire during [17–24] present new opportunities. approach simulating experiment then iterating model parameters best fit has elastography [25,26] well indentation [27] can applied well. In this we demonstrate use combined displacement field data, FE modeling properties test.