Table 1

Material properties specified in the finite element models

Material
Elastic modulus (MPa)
Poisson ratio
Total element number
Cross section area (mm2)

Cancellous bone
100
0.2
18185
-
Cortical bone
12000
0.3
6512
-
Endplate
1000
0.4
2361
-
Nucleus pulposus
10
0.4
1281

Posterior elements
3500
0.25
16587
-
Pedicle screw/cage
110000
0.3
6388
-
Annulus fibre layers




Outermost
550
0.3
-
0.7
Second
495
0.3
-
0.63
Third
440
0.3
-
0.55
Fourth
420
0.3
-
0.49
Fifth
385
0.3
-
0.41
Innermost
360
0.3
-
0.30
Ligaments




Lig. long. posterius
70
-
-
20
Lig. flava
50
-
-
60
Lig. intertransversia
50
-
-
10
Lig. interspinalia
28
-
-
35.5
Lig. supraspinalia
28
-
-
35.5
Lig. capsulae
20
-
-
40

Chen et al. BMC Musculoskeletal Disorders 2008 9:88   doi:10.1186/1471-2474-9-88