OUTSIDE-IN VS. INSIDE-OUT: CONTRASTING PATTERNS OF COMPRESSIVE DEFORMATION IN CARTILAGE AND MENISCUS

摘要

The superficial zones of articular cartilage and meniscus are structurally distinct from the rest of the tissue. In cartilage, the superficial zone is characterized by a relatively low proteoglycan content and a relatively high content of fine collagen fibrils oriented parallel to the articular surface [1], resulting in a low compressive modulus at the surface [2, 3]. In meniscus, the superficial zone is characterized by a fine mesh of randomly oriented collagen fibrils [1] while the interior of the tissue consists of bundles of circumferentially oriented collagen I fibers surrounded by a secondary network containing multiple collagen types and proteoglycans [4]. As relatively little is known about the depth-varying mechanical properties of the meniscus, this study aimed to characterize the depth-dependent response of cartilage and meniscal tissue to compression by comparing the two-dimensional strain fields of site-matched tissue pairs.