Bioengineered Interfaces for Peripheral Nerve Sensory Restoration.
TL;DR
Proprioception, the hardest and least measurable sensation to restore, is examined in depth, as are biomimetic, neuromorphic, biohybrid, and machine-learning approaches toward adaptive, closed-loop communication, weighed against their limits to adoption.
Abstract
Peripheral nerve injuries (PNIs) severely impair motor and sensory function, diminishing patient independence and quality of life. Despite decades of research, rehabilitation has prioritized motor recovery and residual function over the sensory restoration essential for embodiment, intuitive control, and natural movement. This lack of feedback drives poor prosthetic integration, high cognitive demand, and high abandonment rates. This review organizes the field along the translational pathway from injury to functional recovery: the biology of what is lost, strategies that restore the native substrate, the interfaces required when it cannot be rebuilt, and how these strategies are integrated and embodied. Approaches are compared by biological target, sensory function restored, invasiveness, clinical maturity, and limitation, emphasizing how interface properties such as modulus mismatch, charge injection capacity, and foreign body response govern long-term stability and naturalness. Proprioception, the hardest and least measurable sensation to restore, is examined in depth, as are biomimetic, neuromorphic, biohybrid, and machine-learning approaches toward adaptive, closed-loop communication, weighed against their limits to adoption. The review closes with design principles and the challenges they face, from power and scalability to regulatory and ethical hurdles. The future lies in patient-centered interfaces that let individuals not only move, but feel again.