Table 1 Material properties used in finite element model
Component | Element Type | Young Modulus (MPa) | Poisson Ratio | Cross-Sectional Area (mm2) |
|---|---|---|---|---|
Bone | Â | Â | Â | NA |
 Cortical bone | Solid186 | 12,000 | 0.3 |  |
 Cancellous bone | Solid186 | 100 | 0.3 |  |
 Posterior bony elements | Solid186 | 3500 | 0.25 |  |
Intervertebral disc | Â | Â | Â | NA |
 Annulus fibrosus | Solid187 | 1 | 0.499 |  |
 Nucleus pulposus | Solid187 | 4.2 | 0.45 |  |
 Endplate | Solid187 | 1200 | 0.29 |  |
 Cartilage | Shell163 | 35 | 0.4 |  |
Ligaments | Â | Â | Â | Â |
 Anterior longitudinal | link180 | 7.8 | 0.3 | 63.7 |
 Posterior longitudinal | link180 | 10 | 0.3 | 20 |
 Ligamentum flavum | link180 | 15 | 0.3 | 40 |
 Capsular | link180 | 7.5 | 0.3 | 30 |
 Interspinous | link180 | 10 | 0.3 | 40 |
 Supraspinous | link180 | 8 | 0.3 | 30 |
 Intertransverse | link180 | 10 | 0.3 | 1.8 |
Implants | Â | Â | Â | NA |
 Cage (PEEK) | Solid186 | 3600 | 0.3 |  |
 Screws and rods (titanium) | Solid186 | 110,000 | 0.3 |  |