title: Inverse finite element modeling for characterization of local elastic properties in image-guided failure assessment of human trabecular bone.
abstract: The local interpretation of microfinite element (μFE) simulations plays a pivotal role for studying bone structure–function relationships such as failure processes and bone remodeling.In the past μFE simulations have been successfully validated on the apparent level,however, at the tissue level validations are sparse and less promising. Furthermore,intra trabecular heterogeneity of the material properties has been shown by experimental studies. We proposed an inverse μFE algorithm that iteratively changes the tissue level Young's moduli such that the μFE simulation matches the experimental strain measurements.The algorithm is setup as a feedback loop where the modulus is iteratively adapted until the simulated strain matches the experimental strain. The experimental strain of human trabecular bone specimens was calculated from time-lapsed images that were gained by combining mechanical testing and synchrotron radiation microcomputed tomography(SRlCT). The inverse μFE algorithm was able to iterate the heterogeneous distribution of moduli such that the resulting μFE simulations matched artificially generated and experimentally measured strains.
authors.forename: Alexander
authors.initials: A
authors.lastname: Zwahlen
authors.forename: David
authors.initials: D
authors.lastname: Christen
authors.forename: Davide
authors.initials: D
authors.lastname: Ruffoni
authors.forename: Philipp
authors.initials: P
authors.lastname: Schneider
authors.forename: Werner
authors.initials: W
authors.lastname: Schmolz
authors.forename: Ralph
authors.initials: R
authors.lastname: Muller
mesh_terms: D000328:Adult; D000465:Algorithms; D055119:Elastic Modulus; D020342:Finite Element Analysis; D006801:Humans; D008422:Materials Testing; D013314:Stress, Mechanical; D013904:Thoracic Vertebrae / Q000000981:diagnostic imaging* / Q000502:physiology; D055114:X-Ray Microtomography