This thesis explores the intricate biomechanics of cortical bone remodeling, emphasizing the multifaceted roles of mechanical factors and interstitial fluid dynamics within the framework of porous media theory. The study begins by examining historical and contemporary theories of poroelasticity, focusing on the interactions between various phases in media such as soil, bone, and rocks, which are critical for understanding fluid movement and mechanical interactions within porous media. Central to this analysis is the adaptation of mixture theory and the exploration of Biot's poroelastic theory, which together offer a broader conceptual framework capable of addressing multi-phase interactions inside a mixture and the complex dynamics within cortical bone tissue.
Chapter 2 delves into mixture theory and its subsequent theory, the theory of porous media, refining the analysis of fluid and solid phases within cortical bone by incorporating advanced computational models that include both advection terms and shear stress calculations. This chapter also prioritizes the velocity of the fluid phase over displacement measurements, contrasting with the original theory of porous media, to enhance the understanding of the mechanical stimuli of the fluid phase in cortical bone mixtures.
Building upon the theoretical framework proposed in Chapter 2, Chapter 3 investigates the dynamics of interstitial fluid within cortical bone, focusing on how blood pressure and mass exchange between phases affect interstitial fluid pressure and velocity inside different levels of porosity of cortical bone. This chapter also provides a comprehensive examination of interstitial fluid mass exchange dynamics across different porosity levels within cortical bone, correlating these findings with empirical data.
Chapter 4 extends this study by quantifying interstitial fluid pressure and integrating it with strain energy density to model the mechanical stimuli impacting bone remodeling. This includes a detailed look at how porosity, loading magnitude, and cortical bone anisotropy influence bone remodeling process.
The dissertation concludes by integrating the results from these studies to propose a refined model of cortical bone remodeling that considered interstitial fluid dynamics in the cortical bone remodeling. This comprehensive model captures the various factors affecting interstitial fluid pressure and velocity, integrating these insights with the strain energy density of the solid phase. By addressing previous limitations and incorporating both empirical observations and theoretical predictions, this model enhances the understanding of cortical bone physiology and provides a robust foundation for future research in the biomechanics and mechanobiology of cortical bone remodeling.