Advances in Neuroprosthetic Hand Rehabilitation: Enhancing Tactile Sensation through Soft Skin Compliance and Electrotactile Feedback

Restoration of hand function following upper-limb amputation has transitioned from purely mechanical replacement to sophisticated neural integration. A critical barrier in current prosthetics is the "sensory gap" the lack of biological-like compliance and real-time tactile feedback. This article explores recent breakthroughs in neuroprosthetic design, specifically focusing on the synergy between soft synthetic skin compliance and electrotactile sensory feedback. By employing internal open-pocket architectures in synthetic phalanges, compliance can be increased by over 400%, mimicking the human finger's natural displacement of >2 mm at 2 N of force. When coupled with closed-loop electrotactile systems, these "soft" neuroprosthetics achieve object discrimination accuracies exceeding 97%. This dual approach addresses both the functional and emotional requirements of prosthetic users, paving the way for more natural social interaction and embodiment.