Schofield Jonathon S, Schoepp Katherine R, Williams Heather E, Carey Jason P, Marasco Paul D, Hebert Jacqueline S
Faculty of Engineering, Department of Mechanical Engineering, University of Alberta, Edmonton, Alberta, Canada.
Faculty of Medicine & Dentistry, Division of Physical Medicine & Rehabilitation, University of Alberta, Edmonton, Alberta, Canada.
PLoS One. 2017 Jun 2;12(6):e0178517. doi: 10.1371/journal.pone.0178517. eCollection 2017.
One of the most important factors in successful upper limb prostheses is the socket design. Sockets must be individually fabricated to arrive at a geometry that suits the user's morphology and appropriately distributes the pressures associated with prosthetic use across the residual limb. In higher levels of amputation, such as transhumeral, this challenge is amplified as prosthetic weight and the physical demands placed on the residual limb are heightened. Yet, in the upper limb, socket fabrication is largely driven by heuristic practices. An analytical understanding of the interactions between the socket and residual limb is absent in literature. This work describes techniques, adapted from lower limb prosthetic research, to empirically characterize the pressure distribution occurring between the residual limb and well-fit transhumeral prosthetic sockets. A case series analyzing the result of four participants with transhumeral amputation is presented. A Tekscan VersaTek pressure measurement system and FaroArm Edge coordinate measurement machine were employed to capture socket-residual limb interface pressures and geometrically register these values to the anatomy of participants. Participants performed two static poses with their prosthesis under two separate loading conditions. Surface pressure maps were constructed from the data, highlighting pressure distribution patterns, anatomical locations bearing maximum pressure, and the relative pressure magnitudes. Pressure distribution patterns demonstrated unique characteristics across the four participants that could be traced to individual socket design considerations. This work presents a technique that implements commercially available tools to quantitatively characterize upper limb socket-residual limb interactions. This is a fundamental first step toward improved socket designs developed through informed, analytically-based design tools.
成功的上肢假肢最重要的因素之一是接受腔设计。接受腔必须进行个性化制作，以获得适合用户形态的几何形状，并在残肢上适当分布与假肢使用相关的压力。在较高水平的截肢中，如经肱骨截肢，由于假肢重量增加以及对残肢的身体需求提高，这一挑战被放大。然而，在上肢假肢领域，接受腔制作在很大程度上仍由经验做法主导。文献中缺乏对接受腔与残肢之间相互作用的分析理解。这项工作描述了从下肢假肢研究中借鉴的技术，以实证方式表征残肢与适配良好的经肱骨假肢接受腔之间的压力分布。本文展示了一个分析四名经肱骨截肢参与者结果的病例系列。使用Tekscan VersaTek压力测量系统和FaroArm Edge坐标测量机来获取接受腔 - 残肢界面压力，并将这些值在几何上与参与者的解剖结构进行配准。参与者在两种不同的加载条件下，用他们的假肢摆出两个静态姿势。根据数据构建表面压力图，突出显示压力分布模式、承受最大压力的解剖位置以及相对压力大小。四名参与者的压力分布模式呈现出独特的特征，这些特征可以追溯到个体接受腔设计的考虑因素。这项工作提出了一种技术，该技术利用商用工具定量表征上肢接受腔 - 残肢的相互作用。这是朝着通过基于分析的明智设计工具开发改进接受腔设计迈出的重要第一步。
