Sensorimotor Learning for Control of Prosthetic Limbs

在世界范围内，有超过300万人生活在上肢损失中。近年来的战争、发展中国家的工业化和血管疾病（如糖尿病）导致截肢人数激增。每2,500人中就有一人出生时上肢萎缩。先进的假肢可以在提高上肢丧失者的生活质量方面发挥重要作用，然而，在NHS下无法获得。值得注意的是，许多创伤性肢体丧失的人在其他方面身体健康。如果他们配备先进的假肢并接受心理康复治疗，他们就可以独立生活，对社会支持的需求最小，重返工作岗位并为经济做出贡献。有很多潜在的原因限制了先进假手的广泛临床应用。例如，对假肢使用情况的调查显示，20%的上肢截肢者放弃了假肢，主要原因是这些系统的控制仍然限于一两个动作。此外，将假手切换到适当的抓握模式（例如，使用剪刀）的过程是麻烦的，或者需要特别的解决方案，例如使用智能电话应用。其他原因包括：用户发现他们的假肢不舒服或不适合他们的需要。因此，日常任务，例如系鞋带，目前对于假手使用者来说非常具有挑战性。这些功能缺陷，加上成本高和缺乏具体证据来证明其额外好处，已成为限制先进假手在临床上采用的重大障碍。这个跨学科项目的长期目标是开发并逐步提供下一代假手，以提高用户的生活质量。我们潜在的科学新奇是利用用户学习操作假肢的能力。例如，我们研究了肌肉活动在多大程度上可以偏离控制生物手臂和手部运动的自然模式，以及假肢使用者是否可以学会合成肌肉和假肢之间的功能图。基于我们的试点数据的这种方法，我们假设，实践和感官反馈的可用性可以加速这种学习经验。为了解决这个基本问题，我们将采用体内实验，涉及身体健全的志愿者和临床前工作与肢体丧失的人的探索性研究。从这些研究中获得的见解将为设计新的算法提供信息，以实现对假手的无缝控制。最后，该计划将以学习控制假手的统一理论而告终，该理论将在NHS批准的临床前试验中进行测试。将这种方法成熟为临床可行的解决方案需要一个专门的工程师和科学家团队，以及一个由用户、NHS临床医生、医疗保健和高科技行业组成的联盟。凭借医疗技术挑战奖为我提供的灵活性，我将能够培养和可持续发展我的多学科团队。此外，这笔灵活的资金将使我们能够专注于一个融合的研究计划，最终目标是提供修复解决方案，大大提高NHS批准的临床患者结局指标。在该计划中，我将确定并汇集必要的工程，科学，临床，伦理和监管要素，以形成一个公认的国家中心，用于下一代假肢的发展。这项工作将为我建立仿生肢体中心的15年计划奠定基础。该中心的初衷是作为一种机制，保护工程和科学创新，增加价值，并加速向商业和临床领域的转移。

Worldwide, there are over three million people living with upper-limb loss. Recent wars, industrialisation in developing countries and vascular disease, e.g. diabetes, have caused the number of amputations to soar. Adding to this population each year, one in every 2,500 people are born with upper-limb reduction. Advanced prostheses can play a major role in enhancing the quality of life for people with upper-limb loss, however, they are not available under the NHS. Notably, many people with traumatic limb loss are otherwise physically fit. If they are equipped with advanced prostheses and treated to recover psychologically, they can live independently, with minimal need for social support, return to work and contribute to the economy. There are a plethora of underlying reasons that limit wide clinical adoption of advanced prosthetic hands. For instance, surveys on their use reveal that 20% of upper-limb amputees abandon their prosthesis, with the primary reason being that the control of these systems is still limited to one or two movements. In addition, the process of switching a prosthetic hand into an appropriate grip mode, e.g. to use scissors, is cumbersome or requires an ad-hoc solution, such as using a smart phone application. Other reasons include: users finding their prosthesis uncomfortable or unsuitable for their needs. As such, everyday tasks, such as tying shoe-laces, are currently very challenging for prosthetic hand users. These functional shortcomings, coupled with high costs and lack of concrete evidence for added benefit, have emerged as substantial barriers limiting clinical adoption of advanced prosthetic hands.The long-term aim of this cross-disciplinary programme is to develop, and move towards making available, the next generation of prosthetic hands that can improve the users' quality of life. Our underlying scientific novelty is in utilising users' capability of learning to operate a prosthesis. For instance, we examine the extent to which the activity of muscles can deviate from natural patterns employed in controlling movement of the biological arm and hand and whether prosthesis users can learn to synthesise these functional maps between muscles and prosthetic digits. Basing this approach upon our pilot data, we hypothesise that practice and availability of sensory feedback can accelerate this learning experience. To address this fundamental question, we will employ in-vivo experiments, exploratory studies involving able-bodied volunteers and pre-clinical work with people with limb loss. The insight gained from these studies will inform the design of novel algorithms to enable seamless control of prosthetic hands. Finally, the programme will culminate with a unifying theory for learning to control prosthetic hands that will be tested in an NHS-approved, pre-clinical trial. Maturing this approach into a clinically-viable solution needs a dedicated team of engineers and scientists as well as a consortium of users, NHS-based clinicians and healthcare and high-tech industries. With the flexibility that a Healthcare Technologies Challenge Award affords me, I will be able to nurture and grow sustainably my multi-disciplinary team. In addition, this flexible funding will enable to focus on a converging research programme with the ultimate aim of providing prosthetic solutions that enhance NHS-approved clinical patient outcome measures significantly. Within this programme, I will identify and bring together the engineering, scientific, clinical, ethical and regulatory elements necessary to form a recognised national hub for the development of next-generation prosthetics. This work will provide the foundations for my 15-year plan to establish the Centre for Bionic Limbs. The origin of this Centre will be to act as a mechanism to safeguard engineering and scientific innovations, increase value, and accelerate transfer into commercial and clinical fields.