A finite element analysis of a T12 vertebra in two consecutive examinations to evaluate the progress of osteoporosis

Provatidis, C; Vossou, C; Petropoulou, E; Balanika, A; Lyritis, G

dc.contributor.author	Provatidis, C	en
dc.contributor.author	Vossou, C	en
dc.contributor.author	Petropoulou, E	en
dc.contributor.author	Balanika, A	en
dc.contributor.author	Lyritis, G	en
dc.date.accessioned	2014-03-01T01:29:32Z
dc.date.available	2014-03-01T01:29:32Z
dc.date.issued	2009	en
dc.identifier.issn	1350-4533	en
dc.identifier.uri	https://dspace.lib.ntua.gr/xmlui/handle/123456789/19295
dc.subject	Osteoporosis	en
dc.subject	Finite element analysis	en
dc.subject	Biomechanics	en
dc.subject	Medical imaging	en
dc.subject	Bone	en
dc.subject	Vertebra	en
dc.subject.classification	Engineering, Biomedical	en
dc.subject.other	QUANTITATIVE COMPUTED-TOMOGRAPHY	en
dc.subject.other	BONE-MINERAL DENSITY	en
dc.subject.other	TRABECULAR BONE	en
dc.subject.other	MECHANICAL-PROPERTIES	en
dc.subject.other	STRESS-ANALYSIS	en
dc.subject.other	ANATOMIC SITE	en
dc.subject.other	YIELD STRAIN	en
dc.subject.other	LUMBAR SPINE	en
dc.subject.other	FRACTURE	en
dc.subject.other	RISK	en
dc.title	A finite element analysis of a T12 vertebra in two consecutive examinations to evaluate the progress of osteoporosis	en
heal.type	journalArticle	en
heal.identifier.primary	10.1016/j.medengphy.2008.12.003	en
heal.identifier.secondary	http://dx.doi.org/10.1016/j.medengphy.2008.12.003	en
heal.language	English	en
heal.publicationDate	2009	en
heal.abstract	Osteoporosis is a metabolic disease that causes bones to become fragile and be more likely to break. As basic clinical examinations to detect osteoporosis, dual energy X-ray absorptionnetry (DXA) and quantitative computer tomography (QCT) are used. In the framework of a typical clinical examination, QCT scans were obtained from the T12 vertebra of an elderly woman and osteoporosis was diagnosed. One year later, new QCT scans were obtained in order to evaluate her clinical condition. Using both sets as primary information, two patient-specific finite element (FE) models were created and analyzed under compressive load. Vertebral bone was treated as orthotropic material and its elastic modulus was set as an indirect function of Hounsfield Units (HU). Commercial software for medical image processing and FE analysis, along with in house codes, were used for the mechanical analysis of the FE models. Alterations in the geometry/shape of the vertebra as well as in the distributions of several mechanical quantities were detected between the two FE models. As far as the volume of the vertebra is concerned, it augmented by a percentage of 9.7% while the volume of the vertebral body alone increased by 5.6%. In all the maximum values of the mechanical quantities a measurable reduction was observed (axial compressive displacement: 37.9%, von Mises stress: 23.8%, von Mises strains: 15.1%) and all the investigated distributions in the second FE model became smoother. Finally, the percentage of volume with von Mises strains greater than 4500 mu strain dropped from 8.9%, in the first examination, to 4.9% in the second one. Clinically, the prescribed medication seems to have reinforced the structural stability of the vertebra as a whole and through external remodeling the shape of the vertebra changed in a way that the majority of its volume was relieved from stresses and strains of high magnitude. (C) 2008 IPEM. Published by Elsevier Ltd. All rights reserved.	en
heal.publisher	ELSEVIER SCI LTD	en
heal.journalName	MEDICAL ENGINEERING & PHYSICS	en
dc.identifier.doi	10.1016/j.medengphy.2008.12.003	en
dc.identifier.isi	ISI:000268079200003	en
dc.identifier.volume	31	en
dc.identifier.issue	6	en
dc.identifier.spage	632	en
dc.identifier.epage	641	en