title: Image-based vs. mesh-based statistical appearance models of the human femur: implications for finite element simulations.
abstract: Statistical appearance models have recently been introduced in bone mechanics to investigate bone geometry and mechanical properties in population studies. The establishment of accurate anatomical correspondences is a critical aspect for the construction of reliable models. Depending on the representation of a bone as an image or a mesh, correspondences are detected using image registration or mesh morphing. The objective of this study was to compare image-based and mesh-based statistical appearance models of the femur for finite element (FE) simulations. To this aim, (i) we compared correspondence detection methods on bone surface and in bone volume; (ii) we created an image-based and a mesh-based statistical appearance models from 130 images, which we validated using compactness, representation and generalization, and we analyzed the FE results on 50 recreated bones vs. original bones; (iii) we created 1000 new instances, and we compared the quality of the FE meshes. Results showed that the image-based approach was more accurate in volume correspondence detection and quality of FE meshes, whereas the mesh-based approach was more accurate for surface correspondence detection and model compactness. Based on our results, we recommend the use of image-based statistical appearance models for FE simulations of the femur.
authors.affiliation: Institute for Surgical Technology and Biomechanics, University of Bern, Bern, Switzerland. Electronic address: serena.bonaretti@ucsf.edu.
authors.forename: Serena
authors.initials: S
authors.lastname: Bonaretti
authors.affiliation: Institute for Surgical Technology and Biomechanics, University of Bern, Bern, Switzerland; Asclepios Research Group, INRIA, Sophia Antipolis, France.
authors.forename: Christof
authors.initials: C
authors.lastname: Seiler
authors.affiliation: Ansys, Villeurbanne, France.
authors.forename: Christelle
authors.initials: C
authors.lastname: Boichon
authors.affiliation: Institute for Surgical Technology and Biomechanics, University of Bern, Bern, Switzerland.
authors.forename: Mauricio
authors.initials: M
authors.lastname: Reyes
authors.affiliation: Institute for Surgical Technology and Biomechanics, University of Bern, Bern, Switzerland.
authors.forename: Philippe
authors.initials: P
authors.lastname: Büchler
mesh_terms: D003198:Computer Simulation; D005260:Female; D005269:Femur / Q000033:anatomy & histology* / Q000000981:diagnostic imaging; D020342:Finite Element Analysis; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008297:Male; D008875:Middle Aged; D008953:Models, Anatomic; D009929:Organ Size; D014057:Tomography, X-Ray Computed
keywords: Femur mechanics; Finite element simulations; Image registration; Mesh morphing; Statistical appearance model