Table 2 The material properties specified in the finite element models [8, 12]
Young’s modulus (MPa) | Poisson’s ratio | Cross-sectional area (mm2) | |
|---|---|---|---|
Bony structure | |||
Cortex | 12,000 | 0.3 | – |
Trabecular bone | 100 | 0.2 | – |
Posterior element/graft bone | 3500 | 0.25 | – |
Intervertebral disc | |||
Nucleus pulposus | 1 | 0.49 | – |
Ground substance | 4.2 | 0.45 | – |
Annular fiber | 175 | – | 0.76 |
Ligaments | |||
Anterior longitudinal ligament | 7.8 | – | 63.7 |
Posterior longitudinal ligament | 10 | – | 20 |
Intertransverse ligament | 10 | – | 1.8 |
Ligamentum flavum | 15 | – | 40 |
Interspinous ligament | 10 | – | 40 |
Suprespinous ligament | 8 | – | 30 |
Capsular ligament | 7.5 | – | 30 |
Implants | |||
Bone graft | 3500 | 0.25 | – |
Titanium alloy | 180,000 | 0.28 | – |