Assistive Robotic Hand Augmentation during temporary immobilisation

Hand function is crucial for almost every aspect of daily life, and even temporary impairment can have massive financial and societal implications on both patients independence and employment. The UK is currently estimated to sustain an annual incident rate of 68,000 temporary arm immobilisation cases due to orthopaedic injury, with a projection for a significant increase due to fragility fractures which are particularly impacting the rising older population. Unlike lower-limb assistive options, such as wheelchairs and crutches, there are currently no assistive technologies for temporary upper-limb immobilisation. We seek to target this unmet clinical need and offer a radically different approach to existing options for improving functionality following hand injury. To intelligently meet patient needs while supporting healing and rehabilitation of the affected hand, we propose to increase the functionality of the non-damaged hand during the immobilisation period. During the injury's acute phase, mobilising the injured hand will be painful and impractical. Thus, augmenting the unimpaired hand will immediately enhance functionality to help alleviate temporary disability. This will be done via motor augmentation using a supernumerary robotic device called the Third Thumb, developed by the project contributor Dani Clode Design.

As an extra thumb prosthetic specifically designed to extend the motor abilities of an already fully functional hand, this device allows people to carry out complex daily tasks that normally require bimanual coordination. The project benefits from foundational evidence of our initial research on the neural basis of hand augmentation in healthy participants. We demonstrated that the Third Thumb device allows intuitive control, high levels of embodiment, basic levels of functionality for a lay user with minimal training (<10 minutes), and increased levels of dexterity and motor control with additional customised training. The proposed research project will prepare the development and clinical translation of this unique and easily implemented assistive technology to improve the independence of patients undergoing temporary immobilisation. In collaboration with clinical partners, we will assess the feasibility and safety of this assistive technology by providing a first bespoke prototype.

To ensure patient satisfaction and a feasible implementation of our assistive technology, we will first develop a better understanding of user-experience, by documenting the daily needs of our patient group and by assessing initial device control in a broad and diverse group of naïve users. We will translate the knowledge gained through user-experience analysis into actionable insights for assistive technical development, with the aim to create a prototype tailored to our target population's diverse needs. To enhance motor capabilities, we will develop at-home training protocols for potential users to adapt according to their individual needs, to maximise their independence. Next, we will run a longitudinal trial to generate evidence for the device's safety and successful integration in healthy participants, with emphasis on the experience of 'embodiment'. Here, we will examine potential neural biomarkers for device embodiment and address possible 'side effects' of Thumb intensive use, to ensure its implementation as assistive technology is effective and risk-free. Finally, we will introduce and document Thumb use in individual patients with more complex needs (teenagers and older women) to provide a pre-clinical proof-of-concept for fluent control under dynamic real-life challenges. With our holistic approach, we aim to provide a bespoke solution to a largely unmet clinical need, with the potential to radically improve the daily functionality of the millions of individuals who experience transient hand disabilities annually around the world.