Published online by Cambridge University Press: 22 November 2012
Osteoporosis is a disease characterized by a loss of bone density and an altered bonearchitecture. These modifications lead to an increased risk factor for bone fracture,particularly of the femoral neck. This disease can be explained by a disorder in the boneremodeling process which is triggered by the apparition of micro-cracks within the bone.According to Frost’s theory [1], these micro-cracksappear for a specific local strain threshold. Thus, the knowledge of the microarchitectureand quality of trabecular bone is essential to determine this local strain threshold. Thispaper studied the mechanical trabecular bone behavior of 43 patients diagnosed asosteoporotic whose femoral heads were replaced by hip prosthesis. From each patient, acylinder-shaped of trabecular bone samples was cored. Each sample was scanned by X-raymicro-tomography before a compression test in order to reconstruct a reliableFinite-Element (FE) model of the bone architecture in Abaqus. The force-displacementcurves were recorded for all the samples and calibrated by the experimental responses. Theforce-displacement numerical curves were adjusted to the experimental ones, by modifyingthe tissue microscopic mechanical behavior. This process leads to the determination of thelocal strain threshold responsible for triggering the bone remodeling process.