Quantifying knee joint mechanical exposures and tissue response in high knee flexion

地板水平姿势（例如，跪、蹲）对于许多日常活动（家务、家庭维护、宗教实践）和职业（采矿、儿童保育、地板安装、砖石工程、景观美化）是必不可少的，然而，这些高膝屈曲（膝弯曲）姿势中的膝关节力学和相应的关节组织行为还没有得到很好的理解。虽然一些研究估计这些姿势的膝关节负荷很高（超过健康组织可以承受的水平），但有科学证据支持健康的关节组织可以适应承受高关节负荷的观点。在健康的个体中，观察到人们在长时间跪着后如何移动的变化，这可能在这种适应中发挥作用。我的研究计划旨在：1.推进我的实验室开发的新颖的计算膝关节模型，以最好地表示膝关节运动和整个膝关节运动范围内的负荷。2.创建一个非侵入性的可穿戴系统来测量日常生活活动中地板级任务的频率和持续时间。模拟的关节载荷（来自上述1）和该系统的测量值将用于确定“总载荷”。“拟议的工作将确定健康的、活的膝关节软骨是否表现出不同的应变（变形）行为，这取决于它通常暴露的总负荷。3.测试跪后观察到的运动策略变化是否可能是韧带变化的结果。我的研究计划将为基于解剖学的计算膝关节建模提供创新方法。它将提供第一个经过验证的全屈曲膝关节模型和暴露测量系统。我提出的研究将使加拿大成为这一领域的领导者，通过澄清软骨调节机制，表征与这些姿势相关的负荷，并提供简单的工具来测量使用可穿戴技术假设这些姿势的频率和时间。这项工作很有可能产生超出本提案范围的影响。已确定的与地板水平日常生活活动相关的适应机制可用于未来的预防工作，以减少与跪和蹲间接相关的组织损伤风险。一些国家将工作时膝盖深屈相关的膝关节骨关节炎定为职业病。随着劳动力年龄的增长，预防这种类型的骨关节炎对加拿大人来说变得更加紧迫。 在我的研究计划的学员将应用国家的最先进的建模，运动跟踪和成像方法，以实现这些及时的目标。他们将获得领导力，技术和科学技能，使他们能够在加拿大的工程，科学和医学领域产生重大影响。

Floor-level postures (eg. kneeling, squatting) are essential for many daily activities (household chores, home maintenance, religious practices) and occupations (mining, childcare, floor installation, masonry, landscaping), yet knee joint mechanics and the corresponding joint tissue behaviours in these high knee flexion (knee bending) postures are not well understood. While some research has estimated high knee joint loads in these postures (beyond levels that healthy tissue can withstand), there is scientific evidence to support the idea that healthy joint tissues can adapt to withstand high joint loads. In healthy individuals, changes have been observed in how people move after prolonged kneeling, which may play a role in this adaptation. My research program aims to: 1.Advance the novel, computational knee joint model, developed in my lab, to best represent knee joint movements and loading throughout the full range of knee joint motion. 2.Create a non-invasive, wearable system to measure the frequency and duration of floor-level tasks in activities of daily living. Modeled joint loads (from 1, above) and measurements from this system will be used to determine a "total load." The proposed work will determine if healthy, living knee joint cartilage exhibits different strain (deformation) behaviour depending on the total load to which it is typically exposed. 3.Test whether the changes in movement strategies observed after kneeling could be a result of changes in the ligaments. My research program will contribute innovative approaches to anatomically-based computational knee modeling. It will deliver the first validated full-flexion knee model and exposure measurement system. My proposed research will make Canada a leader in this area by clarifying mechanisms for cartilage conditioning, characterizing the loads associated with these postures, and providing simple tools to measure how often, and for how long, these postures are assumed, using wearable technology. This work has high potential for impact beyond the scope of this proposal. The identified mechanisms for adaptation related to floor-level activities of daily living can be used in future prevention efforts to reduce the risk of tissue damage that has been indirectly linked to kneeling and squatting. Some countries designate knee osteoarthritis associated with deep knee bending at work as an occupational disease. Preventing this type of osteoarthritis becomes more pressing to Canadians as the workforce ages. Trainees in my research program will apply state-of-the-art modeling, motion tracking, and imaging approaches to achieve these timely objectives. They will gain leadership, technical, and scientific skills that will enable them to make a strong impact in the fields of engineering, science, and medicine in Canada.