Dynamic Function of Multi-Articular Joints in the Foot and Ankle

人类的脚是一个令人惊叹的复杂的多关节结构，可以承受巨大的重量，同时无缝地适应地形的变化。脚由二十六块骨头、三十三个关节、二十块肌肉和一百多条韧带组成，能够调整其僵硬程度，使其成为可移动的适配器、刚性杠杆或介于两者之间的东西。由于它的复杂性，人们并不完全了解脚在跑步、跳跃甚至步行等高要求的活动中是如何完成其许多功能的。我们建议利用一种独特的方法，结合高速骨骼成像，使我们能够在脚移动时观察它的内部。这项建议的目的是了解足弓是如何工作的，以及提高我们使用高速骨骼成像技术研究多关节关节的能力。*高速骨骼成像包括拍摄关节复合体的X射线电影，并使用这些信息和3D表面模型来模拟活人执行高要求任务时的骨骼运动。同时，我们的方法还将通过在对象上放置反射标记获取的同步全身运动捕捉数据与X射线数据相结合。同时捕捉这些数据可以让我们在测量全身运动的同时，看到脚部骨骼是如何运动的。这种方法将使我们了解脚在人类运动中的作用。在这个为期五年的提案中，我们将研究脚弓，并质疑一个常见的假设，即它的行为像弹簧一样。同时，我们将开发方法，使我们能够以最小的电离辐射捕捉特定活动，从而最大限度地保护我们的受试者和工作人员的安全。我们还将开发数值方法来非常准确地跟踪脚部紧密排列的小骨骼。*这项工作的结果将让我们了解脚的适应是如何为人类提供进化优势的。我们的结果还将为工程师提供信息，使他们能够设计出更好地模拟脚的功能的假肢。我们在跟踪紧密排列的小骨骼方面所做的改进，将使我们和其他人能够研究人类和动物的其他复杂关节系统。最后，该计划的协作性、跨学科性质将为高素质人员提供丰富的培训环境。

The human foot is an amazingly complicated multi-articular structure that can support tremendous weight, while at the same time seamlessly adapting to changes in terrain. Consisting of twenty-six bones, thirty-three joints, twenty muscles, and over one hundred ligaments, the foot is able to adjust its stiffness to become a mobile adapter, a rigid lever, or something in between. Because of its complexity, it is not fully understood exactly how the foot accomplishes its many functions during demanding activities like running, hopping, or even walking. We propose to utilize a unique approach coupled with High-Speed Skeletal Imaging to allow us to look inside the foot while it is moving. The purpose of this proposal is to understand how the arch of the foot works, as well as improve our ability to study multi-articular joints using High-Speed Skeletal Imaging technologies.***High-Speed Skeletal Imaging consists of taking X-Ray movies of a joint complex and using this information along with a 3D surface model to animate bone motion of a living person as they perform demanding tasks. Concurrently, our method also combines synchronized full body motion capture data, acquired by placing reflective markers on the subject, to the X-Ray data. Capturing these data simultaneously allows us to see how the bones in the foot move while measuring motion of the entire body. This method will allow us to understand the foot's role in human locomotion. In this five-year proposal, we will study the arch of the foot and question a common assumption that it behaves as a spring. Simultaneously, we will develop methods that allow us to capture specific activities with minimal ionizing radiation, which maximizes the safety of our subjects and staff. We will also develop numerical methods to track the small, close-packed bones in the foot with great accuracy. ***The results of this work will allow us to learn how adaptations in the foot provided an evolutionary advantage to humans. Our results will also provide Engineers with information that allows them to design prosthetics that better mimic the foot's function. The improvements we make in tracking small, close-packed bones will allow us and others to study other complex joint systems in humans and animals. Finally, the collaborative, interdisciplinary nature of this program will provide a rich training environment for highly qualified personnel.**