Significance of the collagen criss-cross angle distributions in lumbar annuli fibrosi as revealed by finite element simulations
Document typeConference report
Rights accessOpen Access
In the human lumbar spine, annulus fibr osus (AF) fibres la rgely contribute to intervertebral disc (IVD) stability, and deta iled annulus models are required to obtain reliable predictions of lumbar spine biom echanics by finite element (FE) modelling. However, different definitions of collagen orientation coexist in the literature for healthy human lumbar AFs and are indiscrimi nately used in mode lling. Therefore, four AF fibre-induced anisotropy models were bu ilt from reported anatomical descriptions and inserted in a L3-L5 lumbar bi-segment FE model. AF models were respectively characterized by radial, tange ntial, radial and tangentia l, and no fibre orientation gradients. IVD local biomechanics was studied under axial rotation and axial compression. A new parameter, i.e. the Fi bre Contribution Qual ity parameter, was computed in the anterior, lateral, postero-l ateral and posterior AFs of each model, in function of fibre stresses, load distributions, and matrix shear strains. Locally, each AF model behaved differently, affecting the IVD biomechanics. The Fibre Contribution Quality (FCQ) parameter established a direct link between local AF fibre organization and loading, while other biomechanical data did not. It was conc luded that local AF fibre orientations should be modelled in rela tion to other segment characteristics. The proposed FCQ parameter could be used to examine such relations, being, therefore particularly relevant to patient-specifi c models or artificial disc designs.
CitationNoailly, J.; Damien, D. Significance of the collagen criss-cross angle distributions in lumbar annuli fibrosi as revealed by finite element simulations. A: International Symposium on Computer Methods in Biomechanics and Biomedical Engineering. "Proceedings of the 9th International symposium on Computer Methods in Biomechanics and Biomedical Engineering". Valencia: 2010, p. 107-112.