Contributions of lower extremity musculature to hip and knee joint coordination, stability, and regional tissue mechanics

该项目的长期目标是开发一个工程工具和下肢计算模型的研究平台，以建立从组织到整个关节水平的关节力学的全面理解。这项工作的总体愿景是，它将产生有效的信息，以改善减少下肢损伤、治疗和康复战略，从而降低医疗保健费用，提高患者满意度，使加拿大一般人口更舒适地老龄化。这将通过以下目标来解决：目标1)量化个体肌肉对膝关节和髋关节稳定性的贡献，以应对多平面和多关节任务。目的是确定下肢肌肉组织对髋关节和膝关节运动学和动力学的贡献。这项研究将表明每一个下肢肌肉在发起不同类型的运动和稳定关节中的作用。目的2)量化主动和被动加载方案下膝关节和髋关节软组织结构的区域应力和应变分布。在我的实验室开发的一个定制设计的微型ct兼容关节运动模拟器，将被改编，使其能够将活跃的肌肉力量应用于尸体标本。使用基于CT成像的方法，可以计算区域韧带材料的特性。本研究目标的结果将描述肌肉对髋关节和膝关节韧带应力和应变的影响。目的3建立和验证测量关节接触力学的有限元模型。基于图像的有限元模型将在目标2中开发和验证CT扫描。肌肉肌腱将被建模为二维纤维增强膜和非线性弹簧元件，而韧带将被建模为非线性弹簧。在验证之后，将对不同加载条件下的接触力学进行量化和比较。来自目标1的肌肉-肌腱力将被输入到模型中，以模拟活跃的肌肉负荷。我预计这项工作的完成将导致迄今为止最全面的区域组织机械特性映射，以及这些特性如何受到不同类型的生理负荷和周围肌肉组织的影响。

The long-term goal of this program is to develop a research platform of engineering tools and computational models of the lower extremity to build a comprehensive understanding of joint mechanics ranging from the tissue to whole joint levels. The overall vision of this work is that it will produce valid information to improve lower extremity injury reduction, treatment and rehabilitation strategies resulting in reduced health care costs, improved patient satisfaction and more comfortable ageing of the general Canadian population. This will be addressed through the following objectives: Objective 1) Quantify the individual muscle contributions to knee and hip joint stability in response to multi-planar and multi-joint tasks. The purpose this objective is to determine the contributions of the lower extremity musculature to hip and knee joint kinematics and kinetics. This research will indicate the role of each of the lower extremity muscles in initiating different types of motion and stabilizing the joints. Objective 2) Quantify regional stress and strain distributions in knee and hip joint soft tissue structures in response to active and passive loading protocols. A custom designed micro-CT compatible joint motion simulator, developed in my lab, will be adapted so that it is capable of applying active muscle forces to cadaveric specimens. Using a CT imaging based method, regional ligament material properties can be calculated. The results of this research objective will describe the effect of muscle contributions on hip and knee joint ligament stresses and strains. Objective 3 Development and validation of finite element models to measure joint contact mechanics. Image based finite element models will be developed and validated from CT scans taken in objective 2. Muscle tendons will be modelled as two-dimensional fiber reinforced membranes and non-linear spring elements while the ligaments will be modelled as non-linear springs. Following validation the contact mechanics within the joints will be quantified and compared across different loading conditions. The muscle-tendon forces from objective 1 will be input into the models to simulate active muscle loading I anticipate that the completion of this work will result in the most comprehensive mapping of regional tissue mechanical properties to date and how these are affected by different types of physiological loading and the surrounding musculature.