The effect of tissue-engineered cartilage biomechanical and biochemical properties on its post-implantation mechanical behavior

Abstract

The insufficient load-bearing capacity of today's tissue-engineered (TE) cartilage limits its clinical application. Focus has been on engineering cartilage with enhanced mechanical stiffness by reproducing native biochemical compositions. More recently, depth dependency of the biochemical content and the collagen network architecture has gained interest. However, it is unknown whether the mechanical performance of TE cartilage would benefit more from higher content of biochemical compositions or from achieving an appropriate collagen organization. Furthermore, the relative synthesis rate of collagen and proteoglycans during the TE process may affect implant performance. Such insights would assist tissue engineers to focus on those aspects that are most important. The aim of the present study is therefore to elucidate the relative importance of implant ground substance stiffness, collagen content, and collagen architecture of the implant, as well as the synthesis rate of the biochemical constituents for the post-implantation mechanical behavior of the implant. We approach this by computing the post-implantation mechanical conditions using a composition-based fibril-reinforced poro-viscoelastic swelling model of the medial tibia plateau. Results show that adverse implant composition and ultrastructure may lead to post-implantation excessive mechanical loads, with collagen orientation being

Biochemical and biomechanical characterisation of equine cervical facet joint cartilage

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Spatial correlation of native and engineered cartilage components at micron resolution

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How the Structural Integrity of the Matrix Can Influence the Microstructural Response of Articular Cartilage to Compression

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