Regional and Fiber Orientation Dependent Shear Properties and Anisotropic Modeling of Bovine Meniscus

The meniscus is a multiphase material composed of interstitial water, collagen, glycosaminoglycans (GAGs), and fibrochondrocytes [2, 9]. The microstructure of the meniscus consists of superficial randomly orientated fibers providing a smooth lubricating surface, with the deep portion containing circumferentially oriented fibers intermixed with sparse radial tie fibers [12]. This layered morphology evokes an anisotropic material response with regard to axial, radial and circumferential directions relative to primary collagen fibril orientations [1, 4, 6, 8, 10, 13]. In addition to intrinsic fiber orientation influencing mechanical differences in meniscal tissue, GAG and water content have previously been shown to be regionally dependent within the meniscus, elucidating provincial specificity of the applied stress distribution within the joint.