Biomechanical response of the plantar tissues of the foot in healthy and degenerative conditions.

Abstract

This work reports a set of results on the mechanical response of foot plantar tissues in healthy and degenerative conditions during the gait cycle, by means of a computational approach. A three dimensional finite element model of the foot was developed starting from the analysis of biomedical images. Different constitutive models were defined to interpret the mechanical response of the biological tissues. In particular, a specific visco-hyperelastic constitutive formulation was provided for foot plantar soft tissue considering the general features of tissue mechanics. Degenerative phenomena induce histomorphological alterations and modification of the mechanical properties, as stiffening and lower damping capabilities. Different constitutive parameters for healthy and degenerative conditions were identified by the inverse analysis of experimental data from mechanical tests. The three dimensional numerical model interprets the capability of the plantar soft tissue to act under mechanical actions in different conditions during the phases of the gait cycle. Numerical results highlight aspects of the different stress and strain distributions at the heel strike and the midstance of the healthy and degenerative conditions. V.