Influence of Ankle Motion on Bilateral Amputee Gait

我们拟研究假肢踝关节运动对双侧下肢截肢者步态力学的影响。双侧下肢截肢者经常行走时腿僵硬或僵硬，部分原因可能是假肢踝关节的顺应性和活动范围不够。他们可能会尝试通过补偿性动作来克服假肢的缺陷，从而增加他们在步态过程中的能量消耗。大多数关于截肢者步态的文献都是关于单侧截肢者的，但是很难根据单侧截肢者步态的数据确定需要显著改善的区域。与单侧截肢者相比，双侧腿截肢者由于行走时能量需求增加且行走速度较慢，对假肢部件的改进需求更大。在双侧截肢者中，步态期间的假肢性能更容易评估，因为他们在行走时可获得的生理控制选项较少。文献中很少有关于他们康复的结果研究报道，迄今为止还没有发表过关于双侧腿截肢者的定量步态研究。我们将在VA芝加哥运动分析研究实验室对30名双侧经胫（膝盖以下）和经股骨（膝盖以上）截肢者进行定量步态分析，这些截肢者有或没有增加脚踝运动的假体组件。这些组件包括Endolite Multiflex Ankle，用于增加踝关节的背屈/跖屈和内翻/外翻，以及Otto Bock Ankle Torsion Adapter，用于增加横向平面旋转。我们假设增加踝关节运动将显著改善双侧下肢截肢者的步态。我们也将在15位健全人身上研究模拟双侧截肢者的步态，通过给他们配上减少膝关节和踝关节运动的矫形器。我们假设身体健全的人走路时脚踝和膝盖受限，其步态特征与双侧截肢者相似。健全人的步行模式可以作为比较不同类型病理步态的有用基础，我们认为，改变健全人的运动系统可以提供有关病理步态机制的有价值的信息。这项研究的结果将有助于确定当前假肢技术的局限性，这些局限性会抑制截肢者的正常行走模式。

We propose to investigate the effect of prosthetic ankle motion on the mechanics of bilateral lower-limb amputee gait. Bilateral lower-limb amputees often walk with rigid or stiff legs, which may be due in part to insufficient compliance and ranges of motion in their prosthetic ankles. They may attempt to overcome prosthetic deficiencies with compensatory actions that increase their energy expenditure during gait. Most of the literature pertaining to amputee gait is concerned with persons having unilateral amputations, but it is difficult to identify areas where significant improvement is needed based upon data from unilateral amputee gait. Compared with unilateral amputees, persons with bilateral leg amputations have a greater need for improvement in prosthetic componentry because of their increased energy demand as they walk and their low speed of walking. Prosthetic performance during gait is easier to evaluate in bilateral amputees because they have fewer physiological control options available to them while they ambulate. Few outcome studies have been reported in the literature regarding their rehabilitation, and there have been no published quantitative gait studies on bilateral leg amputees to date. We will perform quantitative gait analyses in the VA Chicago Motion Analysis Research Laboratory on 30 bilateral transtibial (below-knee) and transfemoral (above-knee) amputees walking with and without prosthetic components that increase ankle motion. These components include the Endolite Multiflex Ankle to increase ankle dorsiflexion/plantarflexion and inversion/eversion, and the Otto Bock Ankle Torsion Adapter to increase transverse plane rotation. We hypothesize that increased ankle motion will significantly improve the gaits of bilateral lower-limb amputees. We will also study simulated bilateral amputee gait in 15 able- bodied persons by fitting them with orthoses that minimize knee and ankle motion. We hypothesize that able-bodied persons walking with constrained ankles and knees will have gait characteristics similar to bilateral amputees. The able-bodied walking pattern serves as a useful basis of comparison for different types of pathological gait, and we believe that altering the locomotor system of the able-bodied person can yield valuable information concerning the mechanisms of pathological gait. The results from this study will aid in identifying limitations in current prosthetic technology that inhibit normal patterns of walking in amputees.