Table 1

Material Properties Assigned to Various Spinal Components in the Finite Element Model1316

Young's Modulus (MPa)Poisson's Ratio
Cortical bone12000.00.3
Cancellous bone100.00.2
Posterior bone3500.00.25
Annulus (ground)4.20.45
Annulus (fiber)175.0
Nucleus pulposus1.00.499
Anterior ligament7.8 (<12%), 20.0 (>12%)0.3
Posterior ligament10.0 (<11%), 20.0 (>11%)0.3
Ligamentum flavum15.0 (<6.2%), 19.5 (>6.2%)0.3
Transverse ligament10.0 (<18%), 58.7 (>18%)0.3
Capsular ligament7.5 (<25%), 32.9 (>25%)0.3
Interspinous ligament10.0 (<14%), 11.6 (>14%)0.3
Supraspinous ligament8.0 (<20%), 15.0 (>20%)0.3