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dc.contributor.authorAnderson, Dennis Earlen_US
dc.date.accessioned2014-03-14T20:34:34Z
dc.date.available2014-03-14T20:34:34Z
dc.date.issued2005-04-25en_US
dc.identifier.otheretd-04292005-141126en_US
dc.identifier.urihttp://hdl.handle.net/10919/32025
dc.description.abstractSacral insufficiency fractures are an under-diagnosed source of acute lower back pain. A polymethylmethacrylate (PMMA) cement injection procedure called sacroplasty has recently been utilized as a treatment for sacral insufficiency fractures. It is believed that injection of cement reduces fracture micromotion, thus relieving pain. In this study, finite element models were used to examine the mechanical effects of sacroplasty. Finite element models were constructed from CT images of cadavers on which sacroplasties were performed. The images were used to create the mesh geometry, and to apply non-homogeneous material properties to the models. Models were created with homogeneous and non-homogeneous material properties, normal and osteoporotic bone, and with and without cement. The results indicate that the sacrum has a 3D multi-axial state of strain. While compressive strains were the largest, tensile and shear strains were significant as well. It was found that a homogeneous model can account for around 80% of the variation in strain seen in a non-homogeneous model. Thus, while homogeneous models provide a reasonable estimate of strains, non-homogeneous material properties have a significant effect in modeling bone. A reduction in bone density simulating osteoporosis increased strains nearly linearly, even with non-homogeneous material properties. Thus, the non-homogeneity was modeled similarly in both density cases. Cement in the sacrum reduced strains 40-60% locally around the cement. However, overall model stiffness only increased 1-4%. This indicates that the effects of sacroplasty are primarily local.en_US
dc.publisherVirginia Techen_US
dc.relation.haspartDennisAndersonThesis.pdfen_US
dc.rightsI hereby certify that, if appropriate, I have obtained and attached hereto a written permission statement from the owner(s) of each third party copyrighted matter to be included in my thesis, dissertation, or project report, allowing distribution as specified below. I certify that the version I submitted is the same as that approved by my advisory committee. I hereby grant to Virginia Tech or its agents the non-exclusive license to archive and make accessible, under the conditions specified below, my thesis, dissertation, or project report in whole or in part in all forms of media, now or hereafter known. I retain all other ownership rights to the copyright of the thesis, dissertation or project report. I also retain the right to use in future works (such as articles or books) all or part of this thesis, dissertation, or project report.en_US
dc.subjectCT imagesen_US
dc.subjectbone cementen_US
dc.subjectfinite element modelingen_US
dc.subjectsacroplastyen_US
dc.titleAn Investigation of the Mechanical Implications of Sacroplasty Using Finite Element Models Based on Tomographic Image Dataen_US
dc.typeThesisen_US
dc.contributor.departmentEngineering Science and Mechanicsen_US
dc.description.degreeMaster of Scienceen_US
thesis.degree.nameMaster of Scienceen_US
thesis.degree.levelmastersen_US
thesis.degree.grantorVirginia Polytechnic Institute and State Universityen_US
thesis.degree.disciplineEngineering Science and Mechanicsen_US
dc.contributor.committeechairCotton, John R.en_US
dc.contributor.committeememberMadigan, Michael L.en_US
dc.contributor.committeememberGrant, John Wallaceen_US
dc.identifier.sourceurlhttp://scholar.lib.vt.edu/theses/available/etd-04292005-141126/en_US
dc.date.sdate2005-04-29en_US
dc.date.rdate2005-05-11
dc.date.adate2005-05-11en_US


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