A Constitutive Model for the Annulus of Human Intervertebral Disc: Implications for Developing a Degeneration Model and Its Influence on Lumbar Spine Functioning

Table 3

Material properties, geometrical parameters, and elements number of the lumbosacral spine ligaments [42, 48–50].

Ligament	𝐸1 (MPa)	𝐸2	𝜖12	Number of elements	Area (mm^2)
ALL	7.8	20.0	0.12	5	32.4
PLL	1.0	2.0	0.11	5	5.2
LF	1.5	1.9	0.062	3	84.2
ITL	10.0	59	0.18	4	1.8
SSL	3.0	5.0	0.20	3	25.2
Ligament	Spine level	Area (mm^2)	Poisson’s ratio 𝜈	Number of elements	Stiffness 𝑘 (N/mm)
JC	L1-L2	43.8	0.4	6	42.5±0.8
	L2-L3				33.9±19.2
	L3-L4				32.3±3.3
	L4-L5				30.6±1.5
	L5-S1				29.9±22.0
ISL	L1-L2	35.1	0.4	6	10.0±5.2
	L2-L3				9.6±4.8
	L3-L4				18.1±15.9
	L4-L5				8.7±6.5
	L5-S1				16.3±15.0