Development of an Assistive Dynamic Arm Support for a User With Spinal Muscular Atrophy: A Retrospective Analysis after Two Years of Daily Use

People affected by Spinal Muscular Atrophy typically suffer from decreased muscle strength in upper and lower limbs and face many challenges in accomplishing daily activities. This work presents the usercentered design, development, and long-term evaluation after two years of daily use of an assistive dynamic arm support for a specific user suffering from Spinal Muscular Atrophy. The personalized device provides active assistance to switch the user’s elbow between two functional positions and active or passive support of elbow flexion and extension sufficient to conduct activities of daily living such as eating, drinking, controlling the wheelchair or using computers or smartphones. The device was assessed at multiple time steps, whereas the device has shown to be robust with only minimal maintenance required. The user’s satisfaction, measured by the Quebec User Evaluation of Satisfaction with Assistive Technology 2.0 score, was perceived as high (average score between 3.6 and 4.3, possible range 0 to 5) and the Psychosocial Impact of Assistive Devices Scale indicated that the dynamic arm support positively affected the independence, well-being, and quality of life of the user (average score between 0.85 and 1.5, possible range -3 to +3). This work underlines the benefits of a user-centered design approach and longterm evaluations in terms of usability and, consequently, device adoption of assistive devices, as well as the need for adaptability to the individual needs of different users with muscular weakness