Sensitivity analysis of the static response of intervertebral discs around a nonlinear prestressed state

At LMSSC, Paris, October 3rd 2024, 1.30 p.m.

Shouhong Qin
Master student, LMSSC, Cnam, Paris

The intervertebral disc (IVD) is the structure between two vertebrae, and it consists of the nucleusfibrosus and the annulus fibrosus. IVD plays an important role to the compression and torsion motion of the spine. The degenerative disc disease (DDD) could cause low back pain, and it canal so affect the mechanical behavior of the IVD. To better understand the change inside IVD, many experimental studied are done.

The difficulty and the repeatability of performing an experiment to human IVD drive the demand of developing a numerical model of IVD. The goal of this internship is to analyze the influence of the numerical model's parameters by performing the sensitivity analysis, which is carried out in an open-source software called Lagun. The surrogate model is trained and implemented to the sensitivity analysis to improve the efficiency in Lagun.

To perform a sensitivity analysis, the uncertainty of parameters need to be defined in the form of distribution. The distribution of parameters is defined referred to previous studies. The results shows that the hyperelastic material C10 of the annulus fibrosus of IVD is the most influential parameter to the compression response of IVD. The perspective of this study is to consider the viscosity effect of IVD, and estimate the influence of viscous parameters.