Quantifying the relation between aging-related trabecular bone microstructure and mechanical properties with digital volume correlation approach

Abstract

Trabecular bone, a highly porous 3D network of interconnected rods and plates known as trabeculae, plays a critical role in bone strength and integrity. Osteoporosis, a condition commonly associated with aging, leads to deteriorations in bone mass and microarchitecture, manifesting as reduced bone mineral density, thinner trabecular struts, increased trabecular spacing, and a shift from trabecular plates to rods. These microstructural alterations contribute to age-related fragility fractures. To quantitatively explore the link between microstructural changes and the mechanical properties of trabecular bone, we combined mechanical testing with micro-computed tomography (micro-CT) and digital volume correlation (DVC) to measure 3D full-field deformation in trabecular bone samples from healthy and osteoporotic human cadaver vertebrae. Our multi-step mechanical testing characterized strain concentration propagation under axial compressive loading, providing new insights into how microstructural parameters influence trabecular bone’s mechanical strength. This study demonstrates that imaging-based approaches for evaluating bone mechanical strength could serve as an alternative to traditional fracture risk assessment methods, which primarily rely on bone mineral density.