FREEFORM FABRICATION OF TRANSTIBIAL PROSTHETIC SOCKET - PHASE II

本子项目是利用由NIH/NCRR资助的中心赠款提供的资源的众多研究子项目之一。子项目和研究者（PI）可能已经从另一个NIH来源获得了主要资金，因此可以在其他CRISP条目中表示。列出的机构是中心的，不一定是研究者的机构。大多数下肢截肢者的成功康复包括假肢安装和训练。假肢安装成功的关键是一个舒适、合适的窝，但实现这一目标仍然是一个临床挑战，残肢疼痛和窝不适影响了20-55%的下肢截肢者。使用传统假肢技术实现可接受的插座配合需要在劳动密集型，昂贵的过程中进行个人定制成型和制造，这取决于技术假肢供应日益有限的可用性。为了确保截肢者的持续最佳康复，需要替代方法来制造假体插座，以提高假体提供的效率，增强舒适性和贴合性，或降低成本。该项目将继续开发一种新的有前途的方法，即基于选择性激光烧结（SLS）技术的固体自由形状制造（SFF）。SFF允许直接制造假体插座，而无需使用传统技术所需的中间模具和层压过程。该项目的总体长期目标是开发一种临床实用的快速假肢提供系统，该系统将计算机辅助设计与固体自由形状制造技术相结合。该建议建立在我们之前成功演示SFF插座制造可行性的基础上，并将解决其临床可行性的几个关键问题。拟议工作的具体目标是：(1)开发改进的SFF跨胫假体插座设计，允许使用行业标准的塔架，并纳入可变的顺应性元素；(2)确定变壁顺应性元件在提高经胫骨假体窝的舒适性和契合度方面的临床效果；(3)确定SFF插座在长期临床使用中的耐久性和功能。拟议工作的初始阶段将使用迭代工程设计建模评估过程来开发可变遵从性元素和行业标准的塔安装适配器。在第二阶段的工作中，将研究SFF义肢窝的临床评估。可变柔性元件在增强舒适性和贴合性方面的有效性将通过SFF插座与传统层压插座的主题内案例比较研究来确定。SFF插座的耐用性将在12个月的临床现场试验中确定，该插座采用行业标准的塔架安装系统。退伍军人医疗保健系统由于其老年患者人口的性质，是全国截肢者医疗保健的主要提供者之一，并且在改善康复和假肢技术方面一直处于领先地位，这些技术需要为新的和现有的下肢截肢者服务。VA率先开发和实施CAD/CAM和假肢的自动化制造。本研究建立在先前研究的基础上，通过建立使用SFF作为义肢窝的临床可行性。成功的SFF有可能在提供假体窝方面创造一个重大的范式转变。使用SLS的义肢底座的SFF将消除对模具、手工层压和精加工程序的需求，从而朝着快速提供义肢的集成CAD/CAM系统的目标迈出了重要的一步。SLS自由形状制造特别有吸引力，因为它是商业上可用的，并且能够以最小的成本损失创建复杂的几何形状。这种独特的优势大大扩展了开发替代插座设计的选择。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Successful rehabilitation for the majority of lower extremity amputees includes prosthetic limb fitting and training. Critical to the success of prosthetic fitting is a comfortable, well fitting socket, but accomplishing this remains a clinical challenge with residual limb pain and socket discomfort affecting 20-55% of lower limb amputees. Achieving an acceptable socket fit using conventional prosthetic techniques requires individual custom molding and fabrication in a labor intensive, costly process that is dependent on the availability of an increasingly limited supply of skilled prosthetics. Alternative methods of fabricating prosthetic sockets that can improve efficiency in prosthetic provision, enhance comfort and fit, or reduce cost are needed to ensure the continued optimal rehabilitation of the amputee. This project will continue the development of a new promising method of socket fabrication using solid freeform fabrication (SFF) based on selective laser sintering (SLS) technology. SFF allows the direct manufacture of a prosthetic socket without the intermediate molds and laminating process required with conventional techniques. The overall long-term goal of this project is the development of a clinically practical system for rapid prosthetic limb provision that integrates computer-aided design with solid freeform fabrication techniques. This proposal builds on our previous successful demonstration of the feasibility of SFF socket fabrication and will address several key issues that underlie its clinical viability. The specific objectives of the proposed work are: (1) to develop improved designs for SFF transtibial prosthetic sockets that allow the use of industry standard pylon mounts and incorporate variable compliance elements; (2) determine the clinical effectiveness of variable wall compliance elements in enhancing the comfort and fit of transtibial prosthetic sockets; and (3) determine the durability and functionality of SFF sockets during extended clinical use. The initial phase of the proposed work will use an iterative engineering design-modeling-evaluation process to develop variable compliance elements and an industry standard pylon mount adapter. During the second phase of the proposed work, clinical evaluations of SFF prosthetic sockets will be studied. The effectiveness of variable compliant elements in enhancing comfort and fit will be determined using a within-subject case comparison study of SFF sockets with conventional laminated sockets. Durability of SFF sockets that incorporate an industry standard pylon mounting system will be determined during a 12-month clinical field trial. The Veterans Health Care System by nature of its elderly patient population, is one of the nation's major providers of amputee health care and has been a leader in improving the rehabilitation and prosthetic technology needed to serve both new and existing lower extremity amputees. The VA has pioneered the development and implementation of CAD/CAM and automated fabrication of prosthetic limbs. The proposed study builds on this prior research by establishing the clinical viability of using SFF for prosthetic sockets. Successful SFF has the potential to create a major paradigm shift in the provision of prosthetic sockets. SFF of prosthetic sockets using SLS would eliminate the need for molds, hand lamination, and finishing procedures enabling a major step forward toward the goal of an integrated CAD/CAM system of rapid prosthetic limb provision. SLS freeform fabrication is particularly attractive because it is commercially available and has ability to create complex geometries with minimal cost penalty. This unique advantage significantly expands the options for developing alternate socket designs.