Component

Young’s modulus (MPa)

Poisson ratio

Bone

0.001 (ρ = 0)

33,900ρ^2.20 (0 < ρ ≤ 0.27)

5370 + 469 (0.27 < ρ < 0.6)

10,200ρ^2.01 (0.6 ≤ ρ)

0.4

Ligaments

ALL

20

0.3

PLL

20

0.3

TL

59

0.3

CL

33

0.3

LF

20

0.3

ISL

12

0.3

SSL

15

0.3

Screw (titanium)

110,000

0.28

Rod (titanium)

110,000

0.28

Cage (PEEK)

3600

0.25

Cage (titanium)

110,000

0.28

Annulus fibrosus

50

0.45