Predicting Articular Cartilage Constituent Material Properties Following In Vitro Growth Using a Proteoglycan-Collagen Mixture Model

<p><a> </a> A polyconvex continuum-<a>level</a><a id="x-_anchor_2"></a><a> </a><a id="x-_anchor_3"></a> proteoglycan Cauchy stress function was developed based on the continuum electromechanical Poisson-Boltzmann unit cell model for proteoglycan interactions. The resulting proteoglycan model was combined with a novel collagen fibril model and a ground substance matrix material to create a polyconvex constitutive finite element model of a<a>rticular </a>cartilage. The true collagen fibril modulus , and the ground substance matrix shear modulus , were varied to obtain the best fit to experimental tension, confined compression, and unconfined compression data for native explants and explants cultured in insulin-like growth factor-1 (IGF-1) and transforming growth factor-β1 (TGF-β1). Results indicate that culture in IGF-1 results in a weakening of the COL fibers compared to native explants, and culture in TGF-β1 results in a strengthening of the COL fibers compared to native explants. These results elucidate the biomechanical changes in collagen fibril modulus, and ground matrix shear modulus following <em>in vitro</em> culture with IGF-1 and TGF-β1. Understanding the constitutive effects of growth factor stimulated culture may have applications in AC repair and tissue engineering.</p> <a></a>

Name thesis:degree_name

MS in Mechanical Engineering

Discipline thesis:degree_discipline

Mechanical Engineering

Year dc:date.available

2011

Author dc:creator

• Stender, Michael

Contributors dc:contributor

• Stephen Klisch

• Articular Cartilage
• Finite Element Modeling
• Cartilage growth
• Collagen Fiber Modulus.
• Biomechanical Engineering
• Mechanical Engineering

Identifier

10.15368/theses.2011.19

OAI identifier oai:identifier

oai:digitalcommons.calpoly.edu:theses-1489