Development and Kinematic Verification of a Finite Element Model for the Lumbar Spine: Application to Disc Degeneration

Table 2

Mechanical properties of degenerated disc.

Material	Young modulus (MPa)	Poisson coefficient	Element type	Number of elements
Annulus fibrosus	6.0	0.35	Hexahedron	8288
Nucleus pulposus*	1.3	0.4	Tetrahedron	14410
Annulus fiber layers 1	36.0	0.3	Truss**	592
Annulus fiber layers 2	40.8	0.3	Truss**	592
Annulus fiber layers 3	45.5	0.3	Truss**	592
Annulus fiber layers 4	50.3	0.3	Truss**	592
Annulus fiber layers 5	55.0	0.3	Truss**	296

*Elastic material (compressible).
**Only tension.