A numerical study to discriminate between the hydrostatic and deviatoric strain energies impact on cells activity during bone remodelling

Bone remodelling is regulated by specific cellular activities. In particular, the osteocytes are able to transform a mechanical signal into a chemical one and transmit it to the osteoclasts and osteoblasts cells. Additionally, osteocytes are more sensitive to fluid shear than pressure stress. Thus, the mechanical environment, especially the type of external loads applied to the bone structure, may highly influence its evolution over time. In this paper we propose a strain energy based model in which we distinguish between the deviatoric and hydrostatic energy contributions. We study here simple loads and geometries for which the strain energy distribution is homogeneous. From these two cases, we are able to show that when considering more complex structures such as the bone microstructure where the energy distribution is heterogeneous, it is necessary to discriminate between the deviatoric and hydrostatic energy parts.