Full-field measurement of deformation in biological structures such as bones is a promising experimental approach for study of the spatial heterogeneity in mechanical behavior. With the advent of high-resolution, 3-D imaging, digital volume correlation (DVC) allows for the measurement of spatially heterogeneous, 3-D deformation fields throughout entire volumes. For bones such as the vertebra, use of DVC to detect the onset and progression of failure is of direct relevance to the study of osteoporotic fractures. Application of DVC to whole bones, as opposed to machined specimens of bone tissue, involves additional challenges such as the irregular geometry, large data sets, and decreased signal-to-noise ratio. These challenges are addressed in this paper, and the DVC method that results is used to examine yield and post-yield deformations in vertebral compression experiments.
Keywords:
image correlation; full-field measurement; vertebra; spine fracture; deformation