Abstract
In some finite element analysis studies of models of sections of the spine, the three-dimensional solid model is built by assuming symmetry about the mid-sagittal plane of the section, whereas in other studies, the model is built from the exact geometry of the section. The influence of the method used to build the solid model on model parameters, in the case of the cervical spine, has not been reported in the literature. This issue is the subject of this study, with the section being C2–C7, the applied loadings being extension, flexion, left lateral bending, and right axial rotation (each of magnitude 1 Nm), and the model parameters determined being rotation, intradiskal pressure, and facet load at each of the segments. When all the parameter results were considered, it was found that, by and large, the influence of solid model construction method used (exact geometry vs assumption of symmetry about the mid-sagittal plane of the section) was marginal. As construction of a symmetric finite element model requires less time and effort, construction of an asymmetric model may be justified in special cases only.
Highlights
Three-dimensional (3D) geometry of the vertebrae and the disks are obtained from computed tomography (CT) scans taken from the spines of patients or cadavers
Two Finite element (FE) models of a section of the cervical spine (C2–C7) were built, one using the exact geometry of the section (ASYM model) and another in which the geometry was approximated by assuming symmetry about the mid-sagittal plane of the section (SYM model) (Figure 1)
MIMICS (MIMICSÒ Version 14.1; Materialise, Inc., Leuven, Belgium) software package was used for image processing the CT data, IAFEMESH (University of Iowa, IA, USA) software package was used to generate the FE mesh of the model, and ABAQUS (ABAQUSÒ, Version 6.10-2; Abaqus, Inc., Providence, RI, USA) software package was used for the FE analysis
Summary
FE analysis comprises four main features: a mesh of the solid geometry of the model, material properties, constraints, and applied loading. The cervical spine comprises hard tissues (seven vertebrae) and soft tissues. Advances in Mechanical Engineering (intervertebral disks, ligaments, and muscles). Muscles are not considered in the FE analysis with static loading. Three-dimensional (3D) geometry of the vertebrae and the disks are obtained from computed tomography (CT) scans taken from the spines of patients or cadavers. Geometry of ligaments is defined based on their origin and insertion. Material properties of each spinal component can be obtained from literature studies. Applied loading and constraints are similar to those experienced physiologically
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.