Pivot-Flex Foot

公共摘要（Public Abstract） 当处方假肢脚，临床医生面临着令人眼花缭乱的选择，因为超过200种不同的 假脚是可用的。虽然这些传统的假脚主要在矢状面中起作用， 完整脚和踝关节包括一组复杂的关节，其允许在多个运动平面中旋转。一些 这些运动是耦合的，这意味着在一个平面中的旋转引起在另一个平面中的运动。一种这样的耦合是 在矢状面和横切面之间。对于每一步，足底和背屈运动与 柄部相对于脚的外旋转和内旋转。没有义肢可用 来模拟这种自然结合 拟议研究的目的是开发一种模仿自然的被动假肢（弹性足）， 完整肢体的耦合，并确定这种耦合是否可以减少横向平面插座扭矩， 补偿步态生物力学相比，标准护理假体。我们期待长期的 穿着弹性足的结果是软组织和代偿性步态损伤的发生率较低。 为了研究这种耦合的必要性，我们已经建立了一个扭转自适应假体（TAP）， 横向平面和矢状平面之间的耦合比可以用电动机独立地控制。的 TAP可用于发现最佳耦合比，但对于长期日常使用来说有点笨拙。一个更 日常佩戴的强大解决方案是我们按照行业标准制造的被动假肢- 我们计划使用TAP来确定最佳的耦合比，然后构建一个选择， 测试对象是下肢截肢的人。 我们提出的研究有两个具体目标： (1)为了确定横向和矢状面运动之间的最佳耦合比， 新型的扭转自适应假体我们建议进行人类受试者实验（n=15）， 膝盖以下截肢者穿着电机驱动和计算机控制的TAP。参与者将步行到一个 直线和在两个方向上围绕一个圆，而我们改变横向和 矢状面运动受试者将对偶联率不知情。我们假设：（1）耦合比 存在最小化不期望的横向平面套筒扭矩的耦合比，以及（2）将存在耦合比， 截肢者更喜欢该测试的结果将用于指定更实用的枢轴的耦合比， 我们计划在特定目标2中测试柔性脚。 (2)为了确定具有最佳耦合比的被动假体（踝关节-屈曲足）是否可以 与以下相比，降低了横向平面关节窝扭矩和补偿步态生物力学 一个标准护理假肢我们建议设计和建造各种尺寸的可伸缩支脚， 大多数膝下截肢者都能穿的紧身衣。在一项盲法交叉实验中， 受试者（n=15）将安装Flex-Flex Foot和Össur Vari-Flex XC Rotate假体（随机 订购），然后在我们测试之前穿两周。测试将包括走直线 并在两个方向上绕一个圈，同时我们测量他们的步态生物力学。我们假设轴心- Flex Foot将减少横向平面髋臼扭矩和髋关节所做的工作， 标准护理假肢 在拟议的项目之后，我们将有证据表明需要在较低的水平线上提供耦合运动。 假肢如果在这项基于实验室的研究中证明了EST-Flex Foot的有效性，我们将研究长期- 长期结果，即降低软组织和代偿性步态损伤的发生率，并追求商业化 发展

Project Summary (Public Abstract) When prescribing a prosthetic foot, clinicians face a dizzying array of choices as more than 200 different prosthetic feet are available. While these conventional prosthetic feet primarily function in the sagittal plane, the intact foot and ankle comprise a complex set of joints that allow rotation in multiple planes of motion. Some of these motions are coupled, meaning rotation in one plane induces motion in another. One such coupling is between the sagittal and transverse planes. For every step, plantar- and dorsi-flexion motion is coupled with external and internal rotation of the shank relative to the foot, respectively. There is no prosthetic foot available for prescription that mimics this natural coupling. The purpose of the proposed research is to develop a passive prosthesis (Pivot-Flex Foot) that mimics the natural coupling of the intact limb and determine if this coupling can reduce transverse-plane socket torque and compensatory gait biomechanics when compared to a standard-of-care prosthesis. We anticipate the long-term outcomes from wearing a Pivot-Flex Foot are a lower incidence of soft tissue and compensatory gait injuries. To investigate the need for this coupling, we have already built a torsionally adaptive prosthesis (TAP) where the coupling ratio between the transverse- and sagittal-planes can be independently controlled with a motor. The TAP can be used to discover the optimal coupling ratio, but is a bit unwieldy for long-term, everyday use. A more robust solution for daily wear is the Pivot-Flex Foot, a passive prosthesis we have built using industry standards. We plan to use the TAP to identify the optimal coupling ratio and then build a selection of Pivot-Flex Feet for testing by individuals with lower limb amputation. Our proposed research has two specific aims: (1) To identify the optimal coupling ratio between transverse- and sagittal-plane motions using a novel, torsionally adaptive prosthesis. We propose to conduct a human subject experiment (n=15) with below-knee amputees wearing the motor-driven and computer controlled TAP. Participants will walk in a straight line and in both directions around a circle while we vary the coupling ratio between transverse- and sagittal-plane motions. Participants will be blinded to the coupling ratio. We hypothesize that: (1) a coupling ratio exists that minimizes undesirable transverse-plane socket torque and (2) there will be a coupling ratio that amputees prefer. The results from this test will be used to specify the coupling ratio of the more practical Pivot- Flex Feet we plan to test in specific aim 2. (2) To determine if a passive prosthesis with an optimal coupling ratio (Pivot-Flex Foot) can reduce transverse-plane socket torque and compensatory gait biomechanics when compared to a standard-of-care prosthesis. We propose to design and build Pivot-Flex Feet of various sizes and stiffnesses that can be worn by a majority of below-knee amputees. In a blinded crossover experiment, participants (n=15) will be fit with the Pivot-Flex Foot and the Össur Vari-Flex XC Rotate prostheses (random order), and then wear each for two weeks before we test them. The tests will involve walking in a straight line and in both directions around a circle while we measure their gait biomechanics. We hypothesize that the Pivot- Flex Foot will reduce transverse-plane socket torque and the work performed by the hip when compared to a standard-of-care prosthesis. After the proposed project, we will have evidence regarding the need for providing coupled motion in a lower limb prosthesis. If the Pivot-Flex Foot proves efficacious in this laboratory-based study, we will investigate long- term outcomes, namely reduced incidence of soft tissue and compensatory gait injuries, and pursue commercial development.