Topping-off surgery vs posterior lumbar interbody fusion for degenerative lumbar disease: a finite element analysis

Table 1 Material properties of the tissues and implants

	Young’s modulus (MPa)	Poisson’s ratio	Element type	Reference
Cancellous bone	150	0.2	10-node tetrahedral solid element	[1, 2]
Cortical bone	18,000	0.3	10-node tetrahedral solid element	[1, 2]
Nucleus pulposus	2	0.45	10-node tetrahedral solid element	[1, 3]
Annulus fibrosus	8	0.49	10-node tetrahedral solid element	[1, 3]
Implant (Ti-6Al-4 V)	114,000	0.3	10-node tetrahedral solid element	[1, 2]
Bone-cage*	110,000	0.3	10-node tetrahedral solid element	[4, 5]

*Intervertebral fusion cage was used to supplement the K-ROD internal fixation system

ISSN: 1749-799X