Low cost through knee prostheses. TaKeuP Cambodia is one of the world's most landmine affected countries with over 64,000 casualties recorded since 1979 and over 25,000 amputees. Added to this there is also a rise in the number of amputations resulting from road traffic accidents. Currently around 10 million people in South East Asia, India and Sri Lanka need but do not have access to prosthetic and orthotic services and there is a deficit of circa 40,000 professionals. This project directly targets end-users (Prosthetists and amputees) in Cambodia with a view to future expansion into the Philippines, Myanmar, Indonesia and Sri Lanka through strategic partnership with Prosthetics and Orthotics NGO Exceed Worldwide and the Exceed Research Network. We have active collaborations with UK (and European) prosthetics manufacturers (Blatchfords, Otto Bock, Össur), NHS prosthetics and rehabilitation services, and the Defence National Rehabilitation Centre Headley Court.   Recent developments in medical care have resulted in a surgical preference for through-knee amputation where previously above knee amputation was considered preferable. Through-knee amputations allow the socket for the prosthesis to fit on the stump so that the load through the artificial foot and knee is transmitted directly to the end of the stump; this maintains healthy, normal load through the thigh bone. An above knee amputation does not permit this normal loading; the socket has to transmit the loads all the way to the pelvic bone, partially bypassing the thigh, causing pressure sores, inhibiting the range of motion of the amputated limb, and producing bone fragility in the thigh. Therefore, through-knee amputations result in a reduction in pain, fewer incidences of bone formation within muscle (a highly debilitating complication), the ability to bear significantly higher loads, and maintain bone health.  The cost (>£50,000 per device) and maintenance required make modern sockets and powered knee mechanisms designed for through-knee amputees inappropriate for use in low and middle income countries. Current low cost solutions for this provided by the adaptation of Red Cross knee joint prostheses suffer from major limitations such as an inability to be locked in extension, severe compromises on cosmetic appearance resulting in social exclusion, and a very low prosthetic knee joint (due to the long thigh component) producing other functional deficits.  In this project we will develop a low-cost through-knee prosthesis the initial concept for which has been developed by the applicants through prior work with partners in Cambodia. This will be developed further to create a pathway to support the translation of future frugal technology projects (projects that are low cost in terms of manufacture and maintenance) and we will populate this frugal technology pathway with a series of follow on prosthetics and orthotics projects for amputees. Finally, we will ensure that there is a route to harness the frugal technology development for low and middle income countries for the benefit of healthcare in the UK. This project will create a community of researchers, engineers and clinicians developing and translating affordable prostheses. The Global Challenges Research Fund (GCRF) supports cutting-edge research to address challenges faced by developing countries. The fund addresses the UN sustainable development goals. It aims to maximise the impact of research and innovation to improve lives and opportunity in the developing world.