Experimental Measurements of Lumbar Spine Biomechanics to Validate a Finite Element Model of the Lumbar Spine
Author: Michael James Schendel
Publisher:
Published: 1990
Total Pages: 362
ISBN-13:
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Author: Michael James Schendel
Publisher:
Published: 1990
Total Pages: 362
ISBN-13:
DOWNLOAD EBOOKAuthor: Dhruv Jitesh Mehta
Publisher:
Published: 2007
Total Pages: 71
ISBN-13:
DOWNLOAD EBOOKThe aim of the research was to develop a three-dimensional finite element model to study the biomechanical and kinematic characteristics of the human lumbar spine in flexion. An analytical model of the lumbar spine capable of taking into consideration the actual geometry, non-linear material properties and realistic loading would be of benefit in studying normal biomechanics, as well as in-vivo behavior in injured and surgically altered spines. Fundamental to this approach is an accurate model of the spine. This was achieved by modeling the lumbar segments L2-L4 from Computed Tomography (CT) data and analyzing them under loading conditions that best approximated the human lumbar segments in flexion. An in-vitro study was performed for validation of the finite element model. Human lumbar cadaveric spinal segments (L2-L4) were loaded based on test conditions similar to those defined in the finite element analysis. The results of the cadaver biomechanical study and finite element analysis were compared. The results suggest that the model is a valid approach to assessing the range of motion of the L3 segment under flexion. Rotation under lateral bending moments was additionally investigated to provide a thorough validation of the model.
Author: Gregory A. Von Forell
Publisher:
Published: 2012
Total Pages: 0
ISBN-13:
DOWNLOAD EBOOKThe purpose of this work was to determine the possible effects of isolated spinal ligament transection on the biomechanics of the lumbar spine. A finite element model of a lumbar spine was developed and validated against experimental data. The model was tested in the primary modes of spinal motion in the intact condition, followed by comparative analysis of isolated removal of each spinal ligament. Results showed that stress increased in the remaining ligaments once a ligament was removed, potentially leading to ligament damage. Results also showed changes in bone remodeling "stimulus" which could lead to changes in bone density. Isolated ligament transection had little effect on intervertebral disc pressures. All major biomechanical changes occurred at the same spinal level as the transected ligament, with minor changes at adjacent levels. The results of this work demonstrate that iatrogenic damage of spinal ligaments disturbs the load sharing within spinal-ligament complex and may induce significant clinical changes in the spinal motion segment.
Author: Dario Di Maio
Publisher: Springer Nature
Published:
Total Pages: 145
ISBN-13: 3031689011
DOWNLOAD EBOOKAuthor: Enrico Dall’Ara
Publisher: Frontiers Media SA
Published: 2022-09-22
Total Pages: 271
ISBN-13: 2832500382
DOWNLOAD EBOOKAuthor: Tov I. Vestgaarden
Publisher:
Published: 2007
Total Pages:
ISBN-13:
DOWNLOAD EBOOKABSTRACT: This dissertation has two major parts; Analytical and Experimental. The analytical section contains a study using Finite Element Analysis of dynamic instrumentation to demonstrate stress reduction in adjacent level discs. The experimental section contains biomechanical testing of facet fusion allograft technique and finally a comparison between In Vivo and In Vitro intradiscal pressures to determine forces acting on Lumbar spine segment L4-L5. A comprehensive study of available data, technology and literature was done. Conventional fusion instrumentation is believed to accelerate the degeneration of adjacent discs due to the increased stresses caused by motion discontinuity. A three dimensional finite element model of the lumbar spine was obtained which simulated flexion and extension. Reduced stiffness and increased axial motion of dynamic posterior lumbar fusion instrumentation designs results in a ~10% cumulative stress reduction for each flexion cycle. The cumulative effect of this reduced amplitude and distribution of peak stresses in the adjacent disc may partially alleviate the problem of adjacent level disc degeneration. Traditionally a pedicle screw system has been used for fixation of the lumbar spine and this involves major surgery and recovery time. Facet fixation is a technique that has been used for stabilization of the lumbar spine. The cadaver segments were tested in axial rotation, combined flexion/extension and lateral bending. Implantation of the allograft dowel resulted in a significant increase in stiffness compared to control. Facet fusion allograft provides an effective minimally invasive method of treating debilitating pain caused by deteriorated facet joints by permanently fusing them. An In Vitro biomechanical study was conducted to determine the intradiscal pressure during spinal loading. The intradiscal pressures in flexion/extension, lateral bending and axial rotation was compared to In Vivo published data. There is no data that explains the actual forces acting on the spine during flexion, extension, lateral bending or axial rotation. The functional spinal units were tested in combined axial compression and flexion/extension, combined axial compression and lateral bending and combined axial compression and axial rotation using a nondestructive testing method. Overall, this study found a good correlation between In Vivo and In Vitro data. This can essentially be used to make physiological relation from experimental and analytical evaluations of the lumbar spine. It is important to know how much load needs to be controlled by an implant.
Author:
Publisher:
Published: 1977
Total Pages: 892
ISBN-13:
DOWNLOAD EBOOKAuthor: David Moratal
Publisher: BoD – Books on Demand
Published: 2012-03-30
Total Pages: 512
ISBN-13: 9535104748
DOWNLOAD EBOOKFinite Element Analysis represents a numerical technique for finding approximate solutions to partial differential equations as well as integral equations, permitting the numerical analysis of complex structures based on their material properties. This book presents 20 different chapters in the application of Finite Elements, ranging from Biomedical Engineering to Manufacturing Industry and Industrial Developments. It has been written at a level suitable for use in a graduate course on applications of finite element modelling and analysis (mechanical, civil and biomedical engineering studies, for instance), without excluding its use by researchers or professional engineers interested in the field, seeking to gain a deeper understanding concerning Finite Element Analysis.
Author: J. Middleton
Publisher: CRC Press
Published: 2020-09-11
Total Pages: 856
ISBN-13: 1000159450
DOWNLOAD EBOOKContains papers presented at the Third International Symposium on Computer Methods in Biomechanics and Biomedical Engineering (1997), which provide evidence that computer-based models, and in particular numerical methods, are becoming essential tools for the solution of many problems encountered in the field of biomedical engineering. The range of subject areas presented include the modeling of hip and knee joint replacements, assessment of fatigue damage in cemented hip prostheses, nonlinear analysis of hard and soft tissue, methods for the simulation of bone adaptation, bone reconstruction using implants, and computational techniques to model human impact. Computer Methods in Biomechanics and Biomedical Engineering also details the application of numerical techniques applied to orthodontic treatment together with introducing new methods for modeling and assessing the behavior of dental implants, adhesives, and restorations. For more information, visit the "http://www.uwcm.ac.uk/biorome/international symposium on Computer Methods in Biomechanics and Biomedical Engineering/home page, or "http://www.gbhap.com/Computer_Methods_Biomechanic s_Biome dical_Engineering/" the home page for the journal.
Author: A. L. Yettram
Publisher: Manchester University Press
Published: 1989
Total Pages: 298
ISBN-13: 9780719025211
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