Table 1 Material properties of lumbar spine

 Cortical

8-node SOLID185

Ex = 11,300

ν xy = 0.484

–

Ey = 11,300

ν xz = 0.203

–

Ez = 22,000

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

–

 Nucleus pulposus

8-node SOLID185

1.66

0.499

–

 Ground Substance

8-node SOLID185

5.36

0.45

–

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