A method for fracture toughness measurement in trabecular bone using computed tomography, image correlation and finite element method

The fracture resistance of load-bearing trabecular bone is adversely affected by diseases such as osteoporosis. However, there are few published measurements of trabecular bone fracture toughness due to the difficulty of conducting reliable tests in small specimens of this highly porous material.

Professor James Marrow reports in Journal of the Mechanical Behavior of Biomedical Materials a new approach that uses digital volume correlation of X-ray computed tomographs to measure 3D displacement fields in which the crack shape and size can be objectively identified using a phase congruency analysis.  Linear elastic finite analysis of the deformation field around the crack tip provided a good estimate of the critical stress intensity factor for crack propagation.This analysis does not depend on the geometry of the test specimen, nor measurement of the applied load.