Multi-segment FEA of the human lumbar spine including the heterogeneity of the annulus fibrosus
2004 (English)In: Computational Mechanics, ISSN 0178-7675, E-ISSN 1432-0924, Vol. 34, no 2, 147-163 p.Article in journal (Refereed) Published
This study pursues the numerical validation of human lumbar spine segments. By means of the finite element (FE) method, computational analyses are carried out of various load cases. In particular Flexion-Extension, Lateral Bending and Axial Torque are considered. By means of a literature review the underlying constitutive data is verified. In this context, the heterogeneity of the annulus fibrosus, the transversely isotropic stress response of the spinal ligaments and aspects of the FE discretization are particularly emphasized. The numerical results show good agreement with experimental investigations for Extension and Axial Torque for a FE model that accounts for intact human lumbar spine response. In Flexion and Lateral Bending, however, the results of the intact FE-model do not properly account for the experimental data. A good correlation for these load cases can be found by taking disc degeneration into account in the FE-model. This fact shows that tissue degeneration plays a key role in the current validation process and must be accounted for if the lumbar spine specimen is employed for spinal implant evaluation. A degenerated FE-model that represents the stage of degeneration of the specimen and fits the experimental data for all load cases could not be found in this study and warrants further work in this area.
Place, publisher, year, edition, pages
2004. Vol. 34, no 2, 147-163 p.
biomechanics, lumbar spine, nonlinear FEA, heterogeneity, anisotropy, tissue degeneration, finite-element model, motion segment, mechanical-properties, intervertebral joint, disc, ligaments, behavior, moments, fusion
IdentifiersURN: urn:nbn:se:kth:diva-23567DOI: 10.1007/s00466-004-0563-3ISI: 000222604700007OAI: oai:DiVA.org:kth-23567DiVA: diva2:342265
QC 201005252010-08-102010-08-10Bibliographically approved