A Three Dimensional Finite Element Model to Study the Biomechanical and Kinematic Characteristics of the Human Lumbar Spine in Flexion

A Three Dimensional Finite Element Model to Study the Biomechanical and Kinematic Characteristics of the Human Lumbar Spine in Flexion

Author: Dhruv Jitesh Mehta

Publisher:

Published: 2007

Total Pages: 71

ISBN-13:

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The 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.


Biomechanical Implications of Lumbar Spinal Ligament Transection

Biomechanical Implications of Lumbar Spinal Ligament Transection

Author: Gregory A. Von Forell

Publisher:

Published: 2012

Total Pages: 0

ISBN-13:

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The 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.


Determination of Biomechanical Properties and Mechanobiological Behavior of a Spinal Motion Segment with Scoliosis Treatment Using Finite Element Analysis

Determination of Biomechanical Properties and Mechanobiological Behavior of a Spinal Motion Segment with Scoliosis Treatment Using Finite Element Analysis

Author: Bharathwaj Kumar

Publisher:

Published: 2011

Total Pages: 76

ISBN-13:

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Scoliosis is a musculoskeletal abnormality causing complex three dimensional curvatures in the spine. Current surgical treatments for this adolescent spinal deformity are successful but invasive. Potential new treatments that are less invasive are being developed based on altering growth by mechanically redistributing stresses across the vertebral growth plates. In the literature, in vivo and in vitro tests have shown biomechanical changes in the disc and growth plates due to insertion of staple like implants used in these new methods. In order to understand the biomechanics behind these potential new methods, a nonlinear finite element analysis (FEA) is performed and various biomechanical properties of the spinal segment with and without the implant are determinedA three-dimensional FE model of T7-T8 motion segment was developed from a CT scan of a porcine spine and imported to ABAQUS (an FEA software). Various material properties and contact interactions were used from the literature in determining the model that best predicted the available experimental load-displacement curve and the compressive properties of the disc. Bending loads were applied to this FE model to determine the reduction in the motion of the spinal segment. Sensitivity of the implant features were examined against the compressive properties of the disc. Mechanobiological growth models have been partially developed to study various biomechanical factors causing deformities in spine. This available model was utilized in understanding how growth in a normal spine could be influenced due to the presence of these implants.


DHM and Posturography

DHM and Posturography

Author: Sofia Scataglini

Publisher: Academic Press

Published: 2019-08-22

Total Pages: 862

ISBN-13: 0128168838

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DHM and Posturography explores the body of knowledge and state-of-the-art in digital human modeling, along with its application in ergonomics and posturography. The book provides an industry first introductory and practitioner focused overview of human simulation tools, with detailed chapters describing elements of posture, postural interactions, and fields of application. Thus, DHM tools and a specific scientific/practical problem – the study of posture – are linked in a coherent framework. In addition, sections show how DHM interfaces with the most common physical devices for posture analysis. Case studies provide the applied knowledge necessary for practitioners to make informed decisions. Digital Human Modelling is the science of representing humans with their physical properties, characteristics and behaviors in computerized, virtual models. These models can be used standalone, or integrated with other computerized object design systems, to design or study designs, workplaces or products in their relationship with humans. - Presents an introductory, up-to-date overview and introduction to all industrially relevant DHM systems that will enable users on trialing, procurement decisions and initial applications - Includes user-level examples and case studies of DHM application in various industrial fields - Provides a structured and posturography focused compendium that is easy to access, read and understand