Purpose: This paper refers to the diagnostic idea proposed in [11] to measure the parametercalled rate of creep of axillary fold of tissue using modified Harpenden skinfold caliper inorder to distinguish normal and edematous tissue. Our simulations are intended to helpunderstanding the creep phenomenon and creep rate parameter as a sensitive indicator ofedema existence. The parametric analysis shows the tissue behavior under the external load aswell as its sensitivity to changes of crucial hydro-mechanical tissue parameters e.g.permeability or stiffness.Methods: The linear viscoelastic and poroelastic models of normal (single phase) andoedematous tissue (two - phase: swelled tissue with excess of interstitial fluid) implementedin COMSOL Multiphysics environment are used. Simulations are performed within the rangeof small strains for a simplified fold geometry, material characterization and boundaryconditions. The predicted creep is the result of viscosity (viscoelastic model) or pore fluiddisplacement (poroelastic model) in tissue.Results: The tissue deformations, interstitial fluid pressure as well as interstitial fluid velocityare discussed in parametric analysis with respect to elasticity modulus, relaxation time orpermeability of tissue. The creep rate determined within the considered models of tissue iscompared and referred to the diagnostic idea in [11].Conclusion: The results obtained from the two linear models of subcutaneous tissue indicatethat the form of creep curve and the creep rate are sensitive to material parameters whichcharacterize the tissue. However the adopted modelling assumptions point on a limitedapplicability of the creep rate as the discriminant of oedema.
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