Table 1 Material properties of lumbar spine[20–23]

Bone

Cortical

8-node SOLID185

Ex=11300

ν xy=0.484

-

Ey=11300

ν xz=0.203

-

Ez=22000

ν yz=0.203

Gx=3800

Gy=5400

Gz=5400

Cancellous

8-node SOLID185

Ex=140

ν xy=0.45

-

Ey=140

ν xz=0.315

Ez=200

ν yz=0.315

Gx=48.3

Gy=48.3

Gz=48.3

Posterior element

8-nodeSOLID185

3500

0.25

-

Disc

Nucleus pulposus

8-node SOLID185

1.66

0.499

-

Ground Substance

8-node SOLID185

5.36

0.45

-

d=1.12e-007

C₁₀=0.42

C₀₁=0.105

Annulus fibers

2-node LINK10

Outermost

550

-

0.76

Second

495

-

0.5928

Third

412.5

-

0.4712

Innermost

357.5

-

0.3572

Endplate

8-node SOLID185

24

0.4

-

Ligament

2-node LINK10

ALL

7.8

-

24

PLL

10

-

14.4

TL

10

-

3.6

LF

15

-

40

ISL

10

-

26

SSL

8

-

23

CL

7.5

-

30