Effects of Nonlinear Strain-Dependent Permeability and Rate of Compression on the Stress Behavior of Articular Cartilage

摘要: The compressive viscoelastic behavior of articular cartilage, a fiber-reinforced, porous, permeable solid matrix filled with water, is predominately governed by the flow interstitial water within tissue and its exudation across surface. fluid in turn permeability loading imposed upon But for depends nonlinearly on strain; k = ko exp (Me). Here, M nonlinear flow-limiting parameter e dilatation. In this investigation, we studied influence Ro koHA/Uh (where HA elastic equilibrium modulus matrix, h tissue's thickness U rate compression applied onto surface via rigid, free-draining filter) stress history circular plugs cartilage specimens attached to bone. It was found that these two parameters have profound effects predicted history. For very large Ro, become negligible. small M, instantaneous stresses several times larger than those observed at are predicted. This amplification due increase importance relative effect, i.e., leads 0, flow-limit greater 0. Also, theoretical curves predict initially decreases (convex) finally becomes constant. results our 5 percent offset experiments good agreement predictions.