Effect of body weight on the L3 lumbar vertebra with lumbar spinal stenosis in different body-bending degrees: A finite element simulation

Abstract

Lumbar spinal stenosis (LSS) is a common disorder of the human lumbar spine found in elderly people. The disease can cause severe pain in patients, especially when people bend down. The main purpose of this paper is to develop the finite element simulation to study the effect of the weight acting on the lumbar spine when people bend down with various degrees. The computational domains of the three-dimensional L3 lumbar spine were constructed from CT scan images from the intact spine and the spine with LSS. The mathematical model was developed in order to compare the displacement and the von Mises stress between both lumbar spines. The simulations based on the stress equilibrium equation, the strain–displacement relation, and the generalized Hooke’s law were achieved using the finite element method. The result reveals that a high level of displacement occurs around the transverse process and the spinous process of both lumbar vertebrae when a person bends down. Moreover, the investigation shows the von Mises stress that occurs in a patient with LSS is higher than in a normal person. In addition, the von Mises stress increased with an increase in the bending degree.

Keywords

• Lumbar spinal stenosis
• Finite element method
• Three-dimensional model
• Total displacement
• Von Mises stress