Finite Element Analysis of the Visco-Elastic Interaction of the Annulus Fibrosis and Nucleus Pulposis within the Human Intervertebral Joint.
Abstract
An understanding of the mechanical properties and behavior of the intervertebral disc is critical to several current areas of research. Among these are the study of the effects of extreme gravitational forces on the air crews of high performance aircraft and the related problem of spinal injuries due to aircraft ejection. This study was undertaken in order to construct a realistic analytical model of the intervertebral joint using the finite element approach. Experiments have shown that healthy intervertebral joints exhibit creep when subjected to axial load. The focus of this investigation is the behavior and interaction of the nucleus and annulus under loading. An axisymmetric finite element model is employed which incorporates a linear visco-elastic constitutive relation for the annulus and nucleus, based upon a three-parameter Kelvin solid. The visco-elastic constants are found by matching one-dimensional axial experimental data with this two dimensional model. The nucleus, which is composed of a series of concentric lamellae of collagen fibers, has been modelled as a 12 ply structure of orthotropic material.
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 01, 1981
- Accession Number
- ADA111161
Entities
People
- Leslie J. Allen
Organizations
- Air Force Institute of Technology