Karimi Alireza, Shojaei Ahmad, Tehrani Pedram
Department of Mechanical Engineering, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka 819-0395, Japan.
Basir Eye Health Research Center, Tehran 14186, Iran.
J Chem Neuroanat. 2017 Dec;86:15-18. doi: 10.1016/j.jchemneu.2017.07.004. Epub 2017 Jul 15.
The spinal cord as the most complex and critical part of the human body is responsible for the transmission of both motor and sensory impulses between the body and the brain. Due to its pivotal role any types of physical injury in that disrupts its function following by shortfalls, including the minor motor and sensory malfunctions as well as complicate quadriplegia and lifelong ventilator dependency. In order to shed light on the injuries to the spinal cord, the application of the computational models to simulate the trauma impact loading to that are deemed required. Nonetheless, it has not been fulfilled since there is a paucity of knowledge about the mechanical properties of the spinal cord, especially the cervical one, under the compressive loading on the grounds of the difficulty in obtaining this tissue from the human body. This study was aimed at experimentally measuring the mechanical properties of the human cervical spinal cord of 24 isolated fresh samples under the unconfined compressive loading at a relatively low strain rate. The stress-strain data revealed the elastic modulus and maximum/failure stress of 40.12±6.90 and 62.26±5.02kPa, respectively. Owing to the nonlinear response of the spinal cord, the Yeoh, Ogden, and Mooney-Rivlin hyperelastic material models have also been employed. The results may have implications not only for understanding the linear elastic and nonlinear hyperelastic mechanical properties of the cervical spinal cord under the compressive loading, but also for providing a raw data for investigating the injury as a result of the trauma thru the numerical simulations.
脊髓作为人体最复杂和关键的部分,负责在身体和大脑之间传递运动和感觉冲动。由于其关键作用,脊髓的任何类型的物理损伤都会导致功能缺失,包括轻微的运动和感觉功能障碍,以及复杂的四肢瘫痪和终身依赖呼吸机。为了阐明脊髓损伤的情况,应用计算模型来模拟对脊髓的创伤冲击载荷被认为是必要的。然而,由于难以从人体获取该组织,关于脊髓,尤其是颈椎脊髓在压缩载荷下的力学性能的知识匮乏,这一目标尚未实现。本研究旨在通过实验测量24个孤立新鲜样本的人体颈椎脊髓在相对低应变率的无侧限压缩载荷下的力学性能。应力-应变数据显示弹性模量和最大/破坏应力分别为40.12±6.90kPa和62.26±5.02kPa。由于脊髓的非线性响应,还采用了Yeoh、Ogden和Mooney-Rivlin超弹性材料模型。这些结果不仅可能有助于理解颈椎脊髓在压缩载荷下的线性弹性和非线性超弹性力学性能,还可为通过数值模拟研究创伤导致的损伤提供原始数据。