A model for the bio-mechanical stimulus in bone remodelling as a diffusive signalling agent for bones reconstructed with bio-resorbable grafts

Bone remodelling is a self-adaptive process occurring in bone living tissue to optimize its mechanical response to environmental demands. Some cells, namely osteocytes, monitor this response and communicate with other cells, osteoblasts, and osteoclasts, in charge of synthesizing or reabsorbing solid bone in order to acquire the mechanical strength required for bone functioning. In this paper, we employ a diffusive model of a mechanical stimulus to describe at the organ level the mechanisms involved in the transduction of the information and activation of the remodelling process. This stimulus is produced after a bone deformation, and thus we assume it depends on strain energy density. The system that we analyse is a bone sample with a resorbable graft. Mainly, we focus on the interaction between the two components of the system. From a mechanical point of view, we consider a mixture of two solid phases described by a poro-viscoelastic model. The results show a general behaviour that matches the expected outcomes and confirms the usefulness of the proposed model.