A novel finite element model of the ovine lumbar intervertebral disc with anisotropic hyperelastic material properties
A novel finite element model of the ovine lumbar intervertebral disc with anisotropic hyperelastic material properties
复制标题
DOI：
10.1371/journal.pone.0177088
复制
发表时间：
2017-05-04
期刊：
影响因子：
3.7
通讯作者：
Villa, Tomaso
中科院分区：
文献类型：
--
作者：
Casaroli, Gloria;Galbusera, Fabio;Villa, Tomaso
绵羊脊柱是研究人类腰椎生物力学行为的公认模型。事实上，使用动物模型进行体外研究对于研究生物组织的机械行为是必要的，但出于伦理和社会原因，需要减少这种行为。这项研究的目的是建立绵羊腰椎间盘的有限元模型，该模型可能有助于完善对平行体外实验的理解，并可用于预测何时发生机械故障。将各向异性超弹性材料的性能分配给纤维环，并进行析因优化分析，以找出基质和胶原纤维的最佳参数。对于纤维环的基质是基于文献中的实验数据，而对于胶原纤维则是在环状试件上进行拉伸试验。进行了屈伸、侧弯和轴向旋转时的柔度分析。环的前部、侧部和后部有不同的材料特性。后部受压最硬，前部受拉最硬。由于弹性结果与文献数据吻合良好，我们认为该模型适合结合体外和体内测试来研究绵羊腰椎间盘的力学行为。
The Ovine spine is an accepted model to investigate the biomechanical behaviour of the human lumbar one. Indeed, the use of animal models for in vitro studies is necessary to investigate the mechanical behaviour of biological tissue, but needs to be reduced for ethical and social reasons. The aim of this study was to create a finite element model of the lumbar intervertebral disc of the sheep that may help to refine the understanding of parallel in vitro experiments and that can be used to predict when mechanical failure occurs. Anisotropic hyperelastic material properties were assigned to the annulus fibrosus and factorial optimization analyses were performed to find out the optimal parameters of the ground substance and of the collagen fibers. For the ground substance of the annulus fibrosus the investigation was based on experimental data taken from the literature, while for the collagen fibers tensile tests on annulus specimens were conducted. Flexibility analysis in flexion-extension, lateral bending and axial rotation were conducted. Different material properties for the anterior, lateral and posterior regions of the annulus were found. The posterior part resulted the stiffest region in compression whereas the anterior one the stiffest region in tension. Since the flexibility outcomes were in a good agreement with the literature data, we considered this model suitable to be used in conjunction with in vitro and in vivo tests to investigate the mechanical behaviour of the ovine lumbar disc.