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Biomechanical Characterization of the Constitutive Relationship for the Brainstem
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Abstract
Experimental tests using porcine brainstem samples were performed on a custom designed stress relaxation shear device. Tests were performed dynamically at strain rates >1 s−1, to three levels of peak strain (2.5%-7.5%). The directional dependence of the material properties was investigated by shearing both parallel and transverse to the predominant direction of the axonal fibers.
Quasi-linear viscoelastic theory was used to describe the reduced relaxation response and the instantaneous elastic function. The time constants of the reduced relaxation function demonstrate no directional dependence; however, the relative magnitude of the exponential functions and the parameter representing the final limiting value are significantly different for each direction. The elastic function qualitatively demonstrates a dependence on direction.
These results suggest that the brainstem is an anisotropic material. The data provides a starting point for analyzing the directionally dependent nature of brainstem material and can serve as a guide in developing new material models for finite element analysis.
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Citation
Arbogast, K., Meaney, D., and Thibault, L., "Biomechanical Characterization of the Constitutive Relationship for the Brainstem," SAE Technical Paper 952716, 1995, https://doi.org/10.4271/952716.Also In
References
- Dortmans, L. Sauren A. Rousseau E. 1984 Parameter estimation using the quasi-linear viscoelastic model proposed by Fung Journal of Biomechanical Engineering 106 198 203
- Estes, M. McElhaney J. 1970 Response of brain tissue to compressive loading In Fourth ASME Biomechanics Conference. Vol. ASME paper no. 70-BHF-13
- Fallenstein, G. Hulce V. 1969 Dynamic mechanical properties of human brain tissue Journal of Biomechanics 2 217 226
- Fung, Y. 1993 Biomechanics: Mechanical Properties of Living Tissues Springer-Verlag New York
- Galford, J. McElhaney J. 1970 A viscoelastic study of scalp, brain, and dura Journal of Biomechanics 3 211 221
- Green, A. Adkins J. 1970 Large elastic deformations Oxford University Press New York
- Holbourn, A. 1943 Mechanics of head injuries Lancet October 9 438 441
- Myers, B. McElhaney J. Doherty B. 1991 The viscoelastic responses of the hurnan cervical spine in torsion: experimental limitations of quasi-linear theory, and a method for reducing these effects Journal of Biomechanics 24 811 817
- Pamidi, M. 1976 Constitutive properties of brain tissue West Virginia University
- Pamidi, M. Advani S. 1978 Non-linear constitutive relations for human brain tissue Journal of Biomechanical Engineering 100 44 48
- Pudenz, R. Sheldon C. 1946 The lucite calvarium - a method for direct observation of the brain II. Cranial trauma and brain movement Journal of Neurosurgery 3 487 505
- Shuck, L. Advani S. 1972 Rheological response of human brain tissue in shear Journal of Basic Engineering : 905 911
- Unterharnscheidt, F. Higgins L. 1969 Neuropathological effects of translational and rotational acceleration of the head in animal experiments In The Late Effects of Head Injury Walker A. Critchley M. CC Thomas Springfield, IL. 158 167
- Woo, S. Simon B. Kuei S. Akeson W. 1980 Quasi-linear viscoelastic properties of normal articular cartilage Journal of Biomechanical Engineering 102 85 90