Pivot-Flex Foot

项目摘要(公共摘要) 当开假肢处方时，临床医生面临着令人眼花缭乱的200多种不同的选择 可以使用假肢。虽然这些传统的假肢主要在矢状面起作用，但 完整的脚和脚踝由一组复杂的关节组成，这些关节允许在多个运动平面中旋转。其中一些 这些运动是耦合的，这意味着在一个平面上的旋转会导致另一个平面上的运动。其中一种耦合是 在矢状面和横面之间。对于每一步，足底和背部屈曲运动都与 小腿相对于脚的外部旋转和内部旋转。没有假脚可用 寻找模拟这种自然结合的处方。 这项拟议的研究的目的是开发一种被动假体(Pivot-Flex Foot)，模拟自然的 并确定这种联轴器是否可以减少横面套筒扭矩和 与标准护理假体相比，代偿性步态生物力学。我们预计，从长远来看 佩戴Pivot-Flex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需求，我们已经建造了一种扭转自适应假体(TAP)，其中 横向和矢状面之间的耦合比可以用电机独立控制。这个 TAP可以用来发现最佳的耦合比，但对于长期的日常使用来说有点笨拙。A更多 日常佩戴的强健解决方案是Pivot-Flex Foot，这是我们使用行业标准制造的被动假体。 我们计划使用接头来确定最佳联轴器比，然后构建一系列Pivot-Flex脚部，用于 由截肢患者进行测试。 我们提出的研究有两个具体目标： (1)确定横向和纵向平面运动之间的最佳耦合比 新颖的扭转自适应假体。我们建议进行一项人体实验(n=15) 膝下截肢者佩戴电动和计算机控制的丝锥。参与者将穿着一辆 直线和两个方向绕一个圆，同时改变横向和横向之间的耦合比 矢状面运动。参与者将对耦合比视而不见。我们假设：(1)耦合比 存在使不需要的横向平面插座扭矩最小化的情况，以及(2)将存在以下耦合比 截肢者更喜欢。本次试验的结果将被用来指定更实用的枢轴的耦合比- 我们计划在特定的目标2测试柔足。 (2)确定具有最佳联接比的被动假体(Pivot-Flex Foot)是否可以 减少横向平面插座扭矩和补偿步态的生物力学 一种标准护理假体。我们建议设计和制造各种尺寸和尺寸的Pivot-Flex脚 大多数膝下截肢者都可以佩戴的僵硬。在一项盲法交叉实验中， 参与者(n=15)将安装Pivot-Flex足部和Össur Vari-Flex XC旋转假体(随机 订单)，然后在我们测试之前穿两个星期。测试将包括走一条直线 当我们测量他们的步态生物力学时，在两个方向上都绕着一个圆圈。我们假设枢轴- 与屈曲足相比，屈曲足将减少横平面插座扭矩和髋关节所做的功。 标准护理假体。 在拟议的项目完成后，我们将有证据表明需要在较低的位置提供耦合运动 假肢。如果Pivot-Flex足在这项基于实验室的研究中被证明是有效的，我们将研究长期- 长期结果，即软组织和代偿性步态损伤的发生率降低，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.