Gray matter of the bovine cervical spinal cord is mechanically more rigid and fragile than the white matter

Citation
K. Ichihara et al., Gray matter of the bovine cervical spinal cord is mechanically more rigid and fragile than the white matter, J NEUROTRAU, 18(3), 2001, pp. 361-367
Citations number
12
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Neurosciences & Behavoir
Journal title
JOURNAL OF NEUROTRAUMA
ISSN journal
0897-7151 → ACNP
Volume
18
Issue
3
Year of publication
2001
Pages
361 - 367
Database
ISI
SICI code
0897-7151(200103)18:3<361:GMOTBC>2.0.ZU;2-G
Abstract
The gray matter of the cervical spinal cord has been thought to be equally or less rigid than the white matter. Based on this assumption, various stud ies have been conducted on the changes of stress distributions within the s pinal cord under mechanical compression, although the mechanical properties of the white and gray matters had not been fully elucidated. The present s tudy measured the mechanical properties of the white and gray matter of bov ine spinal cords. For both the white and gray matter, the stress-strain cur ves had a nonlinear region, followed by a linear region, and then a region where the stresses plateaued before failure. In the nonlinear region, stres s was not significantly different between the gray and white matter samples (strain similar to0-10 %), while stress and Young's modulus in the gray ma tter was significantly higher than the white matter in the linear part of t he curve. The gray matter ruptured at lower strains than the white matter. These findings demonstrated the gray matter is more rigid and fragile than the white matter, and the conventional assumption (i.e., the white matter i s more rigid than the gray matter) is not correct. We then applied our data to computer simulations using the finite element method, and confirmed tha t simulations agreed with actual magnetic resonance imaging findings of the spinal cord under compression. In future computer simulations, including f inite element method using our data, changes in stress and strain within th e cervical spinal cord under compression would be clarified in more detail, and our findings would also help to elucidate the area which can easily re ceive histologic damage or which could have hemodynamic disorders under mec hanical compression, as well as severity and location of biochemical and mo lecular biological changes.