HandSOME I: Exoskeleton for Assistive Use with Stroke Survivors.

Functional improvement of the upper paretic limb after stroke is mainly determined by improvement of the paretic hand, yet restoration of hand function after stroke often lags behind restoration of more proximal joints, and impairments are often resistant to therapeutic intervention. Currently, the probability of regaining functional use of the impaired hand is low. Most individuals with stroke regain the ability to flex fingers voluntarily, but recovery of voluntary extension is limited. This project further develops the HandSOME I exoskeleton for assistive use and stroke rehabilitation. The HandSOME devices used elastic bands to assist with finger and thumb extension. In many individuals, the ability to grasp and release objects is restored when wearing HandSOME I. Notably, HandSOME I has the potential to be ultra low-profile and easiest to manufacture and fit to patients compared to other devices, making it more suitable for prolonged wear and everyday use. This project develops a new simplified version that decreases the complexity of the design in terms of parts, pin joints, and electrical connections, while also decreasing the difficulty of donning the device. The updated design incorporates several important improvements, including the addition of passive degrees of freedom to enable more flexible grasp patterns by facilitating finger PIP movement and thumb flexion/extension. Developers also integrate a tension system that can be easily adjusted by patients, an electronics interface, and a delivery system so the device can be used straight out of the box. The goals are to reduce complexity, increase the peak torque that can be applied, and decrease the time required to don the device. In the testing phase, 13 individuals with chronic stroke are evaluated for usability and functional gains when wearing the new prototypes. The long-term goal is development of a very low-cost device that can be used straight out of the box as an assistive device during activities of daily living, while simultaneously promoting neurorehabilitation of hand motor control through daily use.