A GLOBAL RELATIONSHIP BETWEEN TRABECULAR BONE MORPHOLOGY AND HOMOGENIZED ELASTIC PROPERTIES

An alternative concept of the relationship bent een morphological and elastic properties of trabecular bone is presented and applied to huma n tissue from several anatomical locations using a digital approach. T he three-dimensional morphology of trabecular bone was assessed with a microcomputed tomography system and the method of directed secants as well as the star volume procedure were used to compute mean intercept length (MIL) and average bone length (ABL) of 4 mm cubic specimens. A ssuming isotropic elastic properties for the trabecular tissue, the ge neral elastic tensors of the bone specimens,were determined using the homogenization method and the closest orthotropic tensors were calcula ted with an optimization algorithm. The assumption of orthotropy for t rabecular bone was found to improve with specimen size and hold within 6.1 percent for a 4 mm cube size. A strong global relationship (r(2) = 0.95) was obtained between fabric and the orthotropic elastic tensor with a minimal set office constants. Mean intercept length and averag e bone length provided an equivalent power of prediction. These result s support the hypothesis that the elastic properties of human trabecul ar bone from an arbitrary anatomical location can be estimated from an approximation of the anisotropic morphology and a prior knowledge of tissue properties.