Abstract:
Fluid flow through the network of bone tissue is hypothesized to be integral in transducing external mechanical forces down to the cellular level. This research utilizes computational fluid dynamics (CFD) modeling of the Navier-Stokes equations and experimental validations to bridge the knowledge gap between tissue and cellular levels. Using increasingly complex physiologic models, the work predicts currently immeasurable properties of the tissue, such as permeability, and the resulting mechanical forces at cellular and subcellular scales. The study finds that the osteocyte cell body experiences a nearly constant pressure and virtually zero shear stress, while its processes are exposed to high gradients of shear stress and pressure. Small discontinuities in the annular wall of the cell processes are found to amplify peak shear stresses up to five times previous predictions, which may resolve the paradox between in vivo and in vitro mechanical force predictions. The knowledge gained is used to improve and design in vitro applications for cell studies and tissue growth.
