Fasciae as mechanical compliant systems in the human body

我的NSERC研究项目的长期目标是开发先进的人体筋膜宏观结构模型，这些模型将被纳入人体有限元模型。这些模型可以用来预测结缔组织筋膜在各种应用中的贡献，特别是肌肉骨骼疾病。由于胸腰筋膜在腰背部疾病中的潜在作用，我们将开发一个腰骶髂（LSI）复合体的三维模型，特别强调胸腰筋膜。这项为期五年的研究计划的具体目标是证明在体温下，由于玻璃化转变温度现象，高应变率可能会损伤胸腰筋膜。本质上，由于玻璃化转变温度的存在，软组织会迅速变得脆弱，并在快速拉伸时表现出急剧增加的刚度，因为胶原蛋白和弹性蛋白在拉伸期间没有时间重新配置。该假设将通过建立一个腰骶髂复合体和胸腰筋膜的三维有限元模型来验证，以估计其在举重任务中的应变和应变率。将使用核磁共振重建技术对筋膜进行详细的解剖研究，并使用差示扫描量热法测量其含水量和玻璃化转变温度。将通过准静态测试确定筋膜的非线性力学性能，并进行动态力学分析，以确定在0至40摄氏度温度范围内的存储模量和损耗模量随应变率的变化。这些数据将提供构建主曲线和WLF模型所需的信息，使我们能够预测各种刺激条件下的组织特性。提出的项目可能会在生物力学领域开辟一个广阔的领域，在许多领域，如眼科，心脏病学，产科和物理治疗的应用。

The long term objective of my NSERC research program is to develop advanced macro-structural models of human fasciae that will be included in finite element (FE) models of the human body. These models can then be used to predict the contribution of connective tissue fasciae in various applications, in particular musculoskeletal disorders. We will develop a three-dimensional model of the lumbo-sacro-iliac (LSI) complex, with a particular emphasis on the thoracolumbar fascia, due to its potential role in low back disorders. The specific goal of this five year research program is to demonstrate that high strain rates could injure the thoracolumbar fascia, at body temperature, because of the glass transition temperature phenomenon. Essentially, due to the existence of a glass transition temperature, a soft tissue would quickly become fragile and exhibit a drastic increase in stiffness when rapidly stretched, because the collagen and elastin proteins do not have time to reconfigure during the stretch. The hypothesis will be tested by creating a three-dimensional finite element model of the lumbo-sacro-iliac complex with the thoracolumbar fascia to estimate its strains and strain rate for a lifting task. Detail anatomical studies will be performed on the fascia using NMR reconstruction techniques and measurements of its water content and glass transition temperature using differential scanning calorimetry. Nonlinear mechanical properties of the fascia will be identified through quasi static tests and dynamic mechanical analysis will be conducted to identify the storage and loss moduli versus strain rate over a temperature range of 0 to 40 degrees Celsius. These data will provide the required information to construct a master curve and a WLF model will allow us to predict tissue properties for various stimuli conditions. The project proposed may opened up a vast domain in biomechanics, with applications in many areas such as ophtalmology, cardiology, obstetrics and physiotherapy.