Articles techniques et présentations

Articular cartilage is composed by a charged solid matrix (proteoglycan and collagen fibres) and an interstitial fluid phase. The permeability of articular cartilage is a function of compression load applied on the tissue, the solid matrix underwent a compaction that decreased its value for increasing deformation. The study of the permeability is very useful to understand the onset and progression of osteoarthritis and to regenerate cartilage by tissue engineering. Permeation studies in vitro are conceptually easy but practically difficult to be performed. Using COMSOL Multiphysics and its poroelasticity module we can perform various types of permeation tests varying the method used for positioning the sample in the test chamber (glued sample and o-ring on top). To understand what is the better way to guarantee the sample seal we evaluated the local strain, the stress and the fluid pressure during the test and we compared these results with the ideal test ones.