Feasibility Evaluation of a Novel Bilateral Hand and Finger Training Device in Patients with Hand Dysfunction: A Preliminary Study.

Background/Objectives: The Synchronized Hand Interface for Neurorehabilitation and Innovation (SHINI) is a mechanical device that uses voluntary movement of the unaffected or less affected upper limb to generate synchronized bilateral hand and finger movements without biological signal detection or electronic control. This exploratory study evaluated SHINI's technical operability and practical limitations during a single supervised session. Methods: Seven participants with hand dysfunction of varied etiologies attempted one 10 min session. Completion status was categorized as completed without therapist intervention, completed with therapist intervention, or not completed; no quantitative acceptability threshold was prespecified. Secondary outcomes were adverse events, overall perceived exertion and upper-limb fatigue assessed using the modified Borg Scale, exploratory pre- and post-session modified Ashworth Scale scores, and participant and therapist feedback. Results: Three participants (42.9%) completed the session without therapist intervention, three (42.9%) completed it with therapist intervention, and one (14.3%) did not complete it. Hand or forearm displacement affected four participants (57.1%), including the participant who discontinued. No adverse events occurred. Perceived exertion and upper-limb fatigue were generally low, no consistent direction of change in modified Ashworth Scale scores was observed, and feedback emphasized the need for improved fixation and adjustability. Conclusions: SHINI showed preliminary technical operability during a single supervised session, but the findings do not establish feasibility for independent or semi-supervised use. With improved fixation and adaptability, SHINI may offer a simple mechanical approach to repetitive bilateral hand training. Repeated-use studies are required to evaluate usability, safety, and clinical effectiveness.