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

点击翻译按钮获取中文摘要

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.