DIRECT MECHANICS ASSESSMENT OF ELASTIC SYMMETRIES AND PROPERTIES OF TRABECULAR BONE ARCHITECTURE

A method is presented to find orthotropic elastic symmetries and const ants directly from the elastic coefficients in the overall stiffness m atrix of trabecular bone test specimens. Contrary to earlier developed techniques, this method does nor require pure orthotropic behavior or additional fabric measurements. The method uses high-resolution compu ter reconstructions of trabecular bone specimens as input for large-sc ale FE-analyses to determine all the 21 elastic coefficients in the ov erall stiffness matrix of the specimen, using a direct mechanics appro ach. An optimization procedure is then used to find the coordinate tra nsformation that yields the best orthotropic representation of this ma trix. The method is illustrated here relative to two trabecular bone s pecimens. The techniques developed here can be used to obtain a comple te characterization of the mechanical properties of trabecular archite cture. With the development of in vivo reconstruction techniques, even in vivo measurements will be possible. Copyright (C) 1996 Elsevier Sc ience Ltd.