Table 2.

Elastic tissue material properties of the AF and NP.

Description	Element type	Young's modulus (MPa)	Poisson's ratio
Normal disc
AF	3D solid (4 node)	2.50	0.40
NP	3D solid (4 node)	1.50	0.49
Moderately degenerated disc
AF	3D solid (4 node)	2.50	0.40
NP	3D solid (4 node)	2.00	0.49
Severely degenerated disc
AF	3D solid (4 node)	5.00	0.20
NP	3D solid (4 node)	4.00	0.25

AF Young modulus represents the modulus of lateral AF.

AF: annulus fibrosus; NP: nucleus pulposus.