Medical & Biological Engineering & Computing

, Volume 45, Issue 10, pp 939–945

Parametric equations to represent the profile of the human intervertebral disc in the transverse plane

Original Article


Computational and finite element models of the spine are used to investigate spine and disc mechanics. Subject specific data for the transverse profile of the disc could improve the geometric accuracy of these models. The current study aimed to develop a mathematical algorithm to describe the profile of the disc components, using subject-specific data points. Using data points measured from pictures of human intervertebral discs sectioned in the transverse plane, parametric formulae were derived that mapped the outer profile of the anulus and nucleus. The computed anulus and nucleus profile were a similar shape to the discs from which they were derived. The computed total disc area was similar to the experimental data. The nucleus:disc area ratios were sensitive to the data points defined for each disc. The developed formulae can be easily implemented to provide patient specific data for the disc profile in computational models of the spine.


Intervertebral disc Transverse geometry Anulus boundary Nucleus boundary 


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Copyright information

© International Federation for Medical and Biological Engineering 2007

Authors and Affiliations

  • J. Paige Little
    • 1
  • M. J. Pearcy
    • 1
  • G. J. Pettet
    • 2
  1. 1.School of Engineering Systems, Institute of Health and Biomedical InnovationQueensland University of TechnologyBrisbaneAustralia
  2. 2.School of Mathematical Sciences, Institute of Health and Biomedical InnovationQueensland University of TechnologyBrisbaneAustralia

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