Session: MSNDC-10-01: Nonlinear and Computational Dynamics Aspects in Biomechanics

Paper Number: 118173

118173 - Finite Element Method-Based Comparison Between Healthy Subject and Patient With Lumbar Interbody Fusion Cage Implant 

Cage subsidence is a common problem in lumbar interbody fusion that can be studied with numerical methods like the Finite Element Method (FEM). Five healthy models were developed to address inter-subject variability and then modified by replacing the whole L4-L5 nucleus with PEEK (polyetheretherketone) linear elastic isotropic material properties to study the effects of the simplified cage in several biomechanical variables. The impact of the new mechanical properties was also studied in an anisotropic simplified PEEK cage, and the healthy models were validated and used as benchmarks against the cage models. It was observed that the simplified PEEK cage model considerably decreased the range of motion of the L4-L5 level and changed the stress distribution by approximately one order of magnitude. Both pure moments and axial loads will be simulated for the five models and their PEEK cage model variations. A 500 [N] preload will be first applied as a follower load to an optimized path made of beam elements [12]. Then, flexion/extension, lateral bending, and axial rotation are applied as rigid body moments to the whole L1 geometry. Axial loads will also be investigated by applying them to L1. The relevant biomechanical variables that will be investigated are intersegmental rotation angle (IRA), facet joint forces (FCF), and intradiscal pressure (IP). Different measurement methodologies were evaluated to study IRA.

Presenting Author: Andres Mena Texas Tech University

Presenting Author Biography: Andres is a first year PhD student in the Department of Mechanical Engineering, Texas Tech University.

Authors:

James Yang Texas Tech University
Paul Egan Texas Tech University
Andres Mena Texas Tech University