Computation models simulating notochordal cell extinction during early ageing of an intervertebral disc.

Department of Mechanical and Manufacturing Engineering, University of Calgary, Alta., Canada.
Computer Methods in Biomechanics and Biomedical Engineering (Impact Factor: 1.79). 03/2011; 14(12):1071-7. DOI: 10.1080/10255842.2010.508037
Source: PubMed

ABSTRACT Lower back pain due to intervertebral disc (IVD) degeneration is a prevalent problem which drastically affects the quality of life of millions of sufferers. Healthy IVDs begin with high populations of notochordal cells in the nucleus pulposus, while by the second stage of degeneration, these cells will be replaced by chondrocyte-like cells. Because the IVD is avascular, these cells rely on passive diffusion of nutrients to survive. It is thought that this transition in cell phenotype causes the shift of the IVD's physical properties, which impede the flow of nutrients. Our computational model of the IVD illustrates its ability to simulate the evolving chemical and mechanical environments occurring during the early ageing process. We demonstrate that, due to the insufficient nutrient supply and accompanying changes in physical properties of the IVD, there was a resultant exponential decay in the number of notochordal cells over time.

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    • "The simulations were performed using the STARS advanced process simulator designed by the Computer Modelling Group (CMG) Ltd. in Calgary, Alberta, to model the flow and reactions of multiphase, multicomponent fluids through porous media [24], [25], [26]. Additionally, STARS has earlier been used to model reactive flow processes in cortical bone [27], [28], [29], [30] as well as through the intervertabral disk [31] "
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