FLUID TRANSPORT AND MECHANICAL-PROPERTIES OF ARTICULAR-CARTILAGE - A REVIEW

This review is aimed at unifying understanding of cartilage viscoelastic properties in compression, in particular the role of compression-dependent permeability in controlling interstitial fluid flow and its contribution to the observed viscoelastic effects. During the previous decade, it was shown that compression causes the permeability of cartilage to drop in a functional manner described by k equals k//0 exp( epsilon M) where k//0 and M were defined as intrinsic permeability parameters and epsilon is the dilatation of the solid matrix ( epsilon equals tr DEL u). Since permeability is inversely related to the diffusive drag coefficient of relative fluid motion with respect to the porous solid matrix, the measured load-deformation response of the tissue must therefore also depend on the non-linearly permeable nature of the tissue. The authors summarize their understanding of this non-linear phenomenon. This understanding of these flow-dependent viscoelastic effects is put into the historical perspective of a comprehensive literature review of earlier attempts to model the compressive viscoelastic properties of articular cartilage.