Rheological Behavior of Fluid Within the Pore Space of Trabecular Bone

The rheological behavior of bone fluid within trabecular porous spaces plays a crucial role in mechanotransduction and, consequently, in bone remodeling. However, most models do not represent its physiological nature. This research aims to characterize the rheological properties of bone fluid flow. Fresh bone samples were harvested from human knees with osteoarthritis (OA), and subjected to tests to evaluate their viscosity using a rheometer. This study revealed that the dynamic viscosity of the fluid varied with time and shear rate, indicating non-Newtonian fluid behavior. Modeling was performed using the power-law model in Python. The power-law model applied in this study proved highly effective in describing the rheological behavior of bone fluid. The fit showed remarkable precision, with a coefficient of determination R² = 0.9995, highlighting the excellent agreement between the experimental data and the model. These results suggest that variations in bone fluid viscosity, induced by mechanical stresses, could modulate osteocyte stimulation and influence bone remodeling in the context of OA. This research represents a significant advance in the understanding of bone fluid, and the knowledge gained could be fundamental for developing new therapeutic strategies in tissue engineering and regenerative medicine.