Fracture strength estimation of L3-L4 intervertebral disc using FEA

Raj Arjun S I,Chandrashekara C V,Parth Goplani

doi:10.21595/vp.2019.20976

Abstract

Mechanical stress and fracture analysis of the human lumbar intervertebral discs are important in assessing disorders related to lower back pain and ageing. Finite element modelling and simulation approaches assist in easier prediction of the disc behaviour under different load conditions. The causes of mechanical failure and morphological changes still remain partially speculative. The present study addresses the issue by developing a finite element model of an L3-L4 lumbar intervertebral disc subjected to different axial compressive loadings. The morphological deformations and stress concentration regions within the disc are analyzed and reported. A mathematical relation is established to estimate the breaking strength of an L3-L4 intervertebral disc, thus indicating the risk of disc failure based on the applied load.

Highlights

The biomechanical analysis of the human body is a challenging area for many researchers
The initial observation made from the analysis is that the maximum deformation of the intervertebral disc occurred at the nucleus pulposus due to its viscous material characteristic
The analysis showed a large amount of fracture failure after the load exceeded a value of 700 N

Summary

Introduction

The biomechanical analysis of the human body is a challenging area for many researchers. Common lower back disorders include strain, lumbar disc degeneration, sciatica, lumbar spinal stenosis and spondylosis These disorders are known to induce high amount of mechanical strain in the intervertebral discs (IVD) of the lumbar vertebrae. Schmidt et al [2] developed FE models of the L4-L5 intervertebral segments for different grades of disc degenerations and investigated the intradiscal pressures and fiber strains under pure and complex loadings. This paper is an attempt to present the essence of mechanical stress analysis approach to the biomechanical evaluation of induced stress in the intervertebral disc under varying axial load conditions. It provides a quantitative evaluation of the risk of disc injuries with respect to the stress induced

Modelling and materials

Results and discussion

Conclusions