ARUP; ISBN: 978-0-9562121-5-3 - CMBBE 2012 - Cardiff University

There was a considerable difference between the error of the displacement maps
computed from Model I and II and the strain maps computed from Model I and Model
III. This could mostly be attributed to two effects: firstly, in Model I a segmented
version of the tomographic image was used for the simulation. Therefore, the warping
was performed using the segmented image as well, which introduces larger errors than
the warping of the gray-scale images; and secondly, the errors of the displacement and
strain maps were consistently larger in regions with spatially inhomogeneous
deformations. This was particularly pronounced in Model I, since the FE simulations
have the same spatial resolution as the original image, while the strain maps have a
resolution of 13.5 voxel. However, in the DIGFA experiments the repeated imaging
leads to smaller errors than warping does.
In conclusion, 3D deformation and strain maps were introduced, optimized and
validated to analyze tomographic images of the cortical bone microstructure in murine
cortical bone. This will allow characterization of deformations and strains during the
initiation and propagation of microcracks at a high spatial resolution.
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