The trend in prosthesis technology is increasingly moving towards expensive and complex high-tech solutions. However, the acceptance of these prostheses is relatively low due to high costs, complexity, and usability challenges, especially among children.
Andreas Trojan, the SwissProsthetics project mentor struggled to find a suitable prosthesis for his 6-year old daughter Sophia, who was born without a left hand (Dysmelie/Amelie). In their experience, the procedure to obtain a first prosthesis was cumbersome, expensive, and solutions to enable playing the violin were not available. In addition, there was no process to change the prosthesis according to activity and finally it lacked a good part of fun factor and did not allow for a feeling of independence.
As a consequence, Andreas sought a collaboration with the ZHAW and later the Wyss Zurich in order to develop and provide a pragmatic solution. The result is a modular system, with exchangeable hand modules for the various activities, which has increased Sophia’s quality of life. She can easily attach the biking hand that helps to activate the brakes, and switch to the swimming hand to allow for symmetric breaststrokes. We are very excited about this outcome and thus would like to enable other children and adults to also benefit from our solution. We strive to deliver our assistive device tool kit, as a medical device class 1 product, to all people in need.
What is special about the project?
Our product is a cost-effective, easy-to-use, lightweight and versatile solution for affected individuals with or without prosthesis. Each person can choose which hand modules they would need based on their interests, e.g. for biking, swimming, and skiing. Other modules will follow based on customer feedback. In addition, we believe our products will reduce physiotherapeutic interventions and increase fitness for work process in a substantial number of people.
Our product is unique because it combines a modular approach for assistive devices with design. As such, it is no longer perceived as a prosthesis but rather as a leisure and fashion product. Furthermore, we combine our individual hand modules with a novel shaft technology that is unprecedented: the system no longer requires the complicated and time-consuming process of fitting the shaft to the stump. Instead, this process is simple, short and swift.
After one testing-day, two long-term test-phases, several user-tests in between and mechanical testing, we are confident to give two shaft systems, called «katta» and «flexi» Open Source. The shaft system «kata» is a parametrized solution for people with middle short arms without a wrist. The shaft system «flexi» is tailor-made and available in the sizes small and medium. This system is for people with functional wrist. The specialty is that they can chose, if they want to use their range of motion for precise activities or if they want a stiff support for rougher activities.
The systems are design in the way that the assembly is easy and that almost all parts are printable, so that the user does not need any special tools to complete it. A mounting bracket adapted to the multi-orientable coupling, is also available to user. So that she/he can build themselves a hand, they need, be it in the CAD-program or handcrafted out of wood, clay, plastic.. etc.
The open-source solution will be available by 2020 on various online platforms. Through collaborations with NGOs such as e-NABLE, we will promote our approach within their online communities to make potential and existing users of prostheses aware of our convenient modular solution. We aim to supply developing countries with this approach and will collaborate with selected partners to facilitate a broad distribution and thus, increasing our impact significantly. Additionally, we managed to find a partner who supports us in distributing 100 pieces of the described “katta” Open-Source solution among the Mexican population with low socio-economic resources. The distribution will take place together with various hospitals and Universities in Mexico City in 2020/21.
The proper market launch of our advanced product shaft and our first module takes place in Q1 of 2021 in Switzerland, following by Austria and Germany in Q2 of 2021, the United States in Q1 of 2022, and finally in Q1 of 2023 in the rest of Europe. Its distribution will be achieved through selected prosthetist partners.
Master Thesis Fabian Schollenberger
Persons involved in the project
Last update to this project presentation 27.04.2021