Regenerative peripheral nerve interfaces for improving activities of daily living in people with upper limb amputations - there are millions of people worldwide with debilitating upper limb amputations

The University of Michigan received a $605,832 Cooperative Agreement from the National Institute of Neurological Disorders and Stroke under the Extramural Research Programs in the Neurosciences and Neurological Disorders program (CFDA 93.853), awarded September 15, 2025, with completion targeted for August 31, 2027. The award funds the development and clinical testing of a regenerative peripheral nerve interface (RPNI) control system designed to enable intuitive, multi-articulated prosthetic hand control for individuals with upper limb amputations. The research addresses regulatory approval requirements and validates a portable wearable device capable of processing signals from RPNIs and residual muscles to improve activities of daily living through a take-home pilot clinical trial involving six participants.

The project encompasses two phases: a UG3 development phase focused on enabling advanced prosthetic functionality through a small wearable signal-processing device, and a UH3 clinical phase designed to determine whether intramuscular electromyography signals with RPNI integration reliably improve functional outcomes and to compare performance against surface electromyography-based control systems. Blue Arbor Technologies, Inc., a sub-awardee, provides FDA-compliant wearable sensing hardware, surface electromyography electrodes, prosthetic receiver components, and firmware/software support manufactured to ISO 13845 standards. The research partnership includes additional industry collaborators (Össur and Synapse Biomedical) to ensure future commercial manufacturability and clinical viability of the developed system.

While electrical signals from residual muscle can provide some function, every person with amputation is missing muscles, and therefore missing a variety of important functions. Our group has demonstrated a novel method for obtaining signals from independent nerve fascicles in humans, which we call the regenerative peripheral nerve interface (rpni). The small muscle grafts degenerate, regenerate, revascularize, and reinnervate utilizing natural biologic processes. Our long-term goal is to make nerve-controlled prostheses widely available, such that multi-articulated hands can be controlled as dexterously and intuitively as an anatomic limb. The objective of the present application, which represents our proposed next step, is to obtain the necessary regulatory approvals to conduct a pilot take- home clinical trial of a portable control system for recording intramuscular signals from rpnis and residual muscles in 6 participants with upper limb loss. In the UG3 portion of the study, we will address the following aim: aim 1. Enable advanced prosthetic functionality using a small wearable device to process rpni signals. In the UH3 portion of the study, we will address the following aims: aim 2. Determine whether intramuscular EMG with rpni signals can reliably and intuitively improve activities of daily living. And aim 3. Compare prosthetic use and function during take-home trials of prosthetic controllers using surface pattern recognition and those using pattern recognition of intramuscular electromyography from residual muscles and rpnis. We have partnered with industry (ossur, synapse biomedical, blue arbor technologies) to ensure the system we develop will be safe and manufacturable in the future. We believe successful completion of these aims will motivate commercialization and widespread use of rpnis for prosthetic control.