Peripheral nerve interfaces

Also known as Nerve interfaces, Peripheral nerve electrodes, Regenerative peripheral nerve interfaces (RPNIs)

Electrodes placed on or in nerves outside the brain and spinal cord can pick up a person's movement signals to control a prosthetic limb, and can send electrical pulses that the nerve reads as touch or pressure. Human studies so far are small, with one to four participants each, and the sources reviewed here do not report an approved nerve interface device.

Research and prototypesDemonstratedReviewed 22 Oct 2026
AI illustration · Illustrative scene, not a photograph of the specific device or experiment.

In plain language

Nerves carry signals between the spinal cord and the muscles and skin of the arms and legs. Peripheral nerve interfaces are electrodes placed on or in these nerves. Some sit around the outside of a nerve like a cuff, some reach into the nerve to contact small bundles of nerve fibres, and some use a small muscle graft that grows around a cut nerve and passes its signals on.

The aim is two-way communication. Electrodes can record the signals a person would have sent to move a missing hand, and use them to drive a prosthesis. They can also send pulses back along the nerve so that the person feels touch, pressure or movement in the missing hand. Early human studies show that both directions can work, but they involve very few people. The review by Tian and colleagues (2024) reports follow-up of one to five or more years, while many studies last only weeks.

Technical explanation

Peripheral nerve interfaces fall into three broad groups. Extraneural cuff electrodes wrap around the outside of a nerve without entering it, which limits damage to the nerve but also limits how selectively they reach individual fibre groups. Intraneural and intrafascicular electrodes, such as the Utah Slanted Electrode Array (USEA) and multichannel intrafascicular electrodes, pass into the nerve or its bundles (fascicles) to get closer to individual fibres. Tian and colleagues (2024) note that direct interfaces of this kind have limitations related to nerve specificity, tissue injury, axonal degeneration and scar tissue formation.

Regenerative peripheral nerve interfaces (RPNIs) take a different route. A transected nerve is wrapped in a free muscle graft, which reinnervates and acts as what Tian and colleagues (2024) describe as a biological amplifier of the peripheral nerve signal. In a study of four patients, Vu and colleagues (2020) reported large signal-to-noise ratios from RPNI electromyography in two, and contraction of the grafts during phantom finger flexion in two others, with ultrasound confirming reinnervation in two. Wallace and colleagues (2026) compared implanted electrodes in RPNIs with dry surface electrodes in two participants and found higher per-bin classification accuracy for the implanted electrodes.

Stimulation is less mature than recording. Tan and colleagues (2014) used cuff electrodes to produce stable touch-like sensations for more than a year in two people. Raspopovic and colleagues (2014) used intrafascicular electrodes in one amputee to evoke sensory feedback during real-time grasp. Wendelken and colleagues (2017) and Page and colleagues (2021) used temporary USEAs to evoke many proprioceptive and cutaneous percepts. The 2021 authors reported above-chance blinded discrimination but also noted that trial numbers per condition were too small to exclude false negatives.

What the evidence says

Each statement is typed by the strength of its evidence and linked to the source that supports it.

Demonstrated Shown in a published experiment, test or shipping product.

Two people with upper-limb amputation who had cuff electrodes implanted around peripheral nerves reported stable, natural-feeling touch in their phantom hands for more than a year, including tapping, constant pressure, light moving touch and vibration.

Sources: [1] · Abstract

In one amputee, multichannel intrafascicular electrodes in the median and ulnar nerve fascicles delivered sensory feedback from a hand prosthesis during real-time grasp control; the participant modulated grip force across three levels and distinguished the stiffness and shape of three objects.

Sources: [2] · Abstract · medium confidence

In two people with long-standing upper-arm amputations, two 100-channel Utah Slanted Electrode Arrays implanted for 4 to 5 weeks, one in the median nerve and one in the ulnar nerve, evoked up to 131 proprioceptive and cutaneous hand percepts, and a real-time decode achieved control of five degrees of freedom.

Sources: [3] · Abstract

In three transradial amputees with USEAs in their arm nerves for 4 to 13 weeks, discrimination of cutaneous and proprioceptive percepts by location, quality and intensity was significantly greater than chance. The authors could not rule out false negatives because they did not have enough trials for each condition, and one post-hoc intensity analysis without the no-stimulation condition was not statistically significant.

Sources: [4] · Abstract, Results and Limitations · medium confidence

Using signals from regenerative peripheral nerve interfaces, a prosthetic hand was controlled in real time for up to 300 days without recalibrating the control algorithm. In a four-patient study, RPNI electromyography in two patients had large signal-to-noise ratios, and ultrasound confirmed functional reinnervation of the RPNIs in two patients.

Sources: [5] · Abstract · medium confidence

In two participants, implanted electrodes in RPNIs reached per-bin classification accuracy of 82.1% and 91.2% in still conditions, compared with 58.2% and 67.1% for dry surface electrodes, and one participant completed a wrist-rotation coffee task 41.26 seconds faster with implanted electrodes than with surface electrodes.

Sources: [7] · Results · medium confidence

The human studies cited in this profile enrolled between one and four participants each, so none is large enough to estimate how often these methods work across people.

Sources: [1], [2], [3], [4], [5], [7]

Reported, unverified Stated by a company or team but not independently confirmed.

Tian and colleagues (2024) state that direct peripheral nerve interfaces face limitations of nerve specificity, tissue injury, axonal degeneration and scar tissue formation, and that the motor signals they give have low signal-to-noise ratios, which they consider impractical for long-term clinical use.

Sources: [6] · medium confidence

The review by Tian and colleagues (2024) reports that signals from RPNIs in clinical participants were stable or increasing over one to five or more years, with no serious adverse events related to the intervention.

Sources: [6] · medium confidence

Limitations and open problems

  • Human studies are small: the sources reviewed here enrolled between one and four participants per study, and the single-amputee study of Raspopovic and colleagues (2014) cannot show how often the method works.
  • The USEA studies used temporary arrays implanted for 4 to 5 weeks (Wendelken and colleagues, 2017) and 4 to 13 weeks (Page and colleagues, 2021), so they do not show long-term safety or performance.
  • Penetrating electrodes can injure nerve tissue, and direct nerve interfaces face axonal degeneration and scar formation (Tian and colleagues, 2024).
  • Sensations are not yet precise: the 2021 authors could not control intensity or quality in location-only trials (Page and colleagues, 2021).
  • The sources reviewed for this profile do not report an approved nerve interface device, so the field remains at research stage.

Possible future uses

Speculative

Ideas, not predictions. None of these has been demonstrated.

  • Everyday prostheses that give a continuous sense of touch and grip force, if long-term studies confirm the short-term results in small groups.
  • Combined RPNI and implanted-electrode systems that control several hand and wrist joints at once outside the laboratory.
  • Nerve-based feedback that lets a person feel virtual or remote objects through their own nerves, for use in training or telepresence.

Timeline

  1. Feb 2014Raspopovic and colleagues report intrafascicular electrodes giving one amputee sensory feedback during real-time grasp control of a hand prosthesis. Sources: [2]
  2. 1 Oct 2014Tan and colleagues report that cuff electrodes gave two people with upper-limb amputation stable touch perception in their phantom hands for more than a year. Sources: [1]
  3. 25 Nov 2017Wendelken and colleagues report two 100-channel USEAs, one each in the median and ulnar nerves of two people, evoking up to 131 proprioceptive and cutaneous percepts. Sources: [3]
  4. Mar 2020Vu and colleagues report real-time control of a prosthetic hand using RPNI signals for up to 300 days without recalibration. Sources: [5]
  5. 5 Feb 2026Wallace and colleagues report that implanted electrodes in RPNIs outperform dry surface electrodes for multi-joint hand and wrist control in two participants. Sources: [7]

Glossary

Peripheral nerve
A nerve outside the brain and spinal cord that carries signals to and from the limbs, skin and organs.
Cuff electrode
An electrode that wraps around the outside of a nerve without going into it.
Intrafascicular electrode
An electrode placed inside a fascicle, a bundle of nerve fibres within a nerve.
Signal-to-noise ratio
How strong a recorded signal is compared with background electrical noise; higher values make decoding easier.

Sources

  1. peer reviewed paper
    A neural interface provides long-term stable natural touch perception
    Daniel W. Tan, Matthew A. Schiefer, Michael W. Keith et al.. Science Translational Medicine, 1 Oct 2014. DOI: 10.1126/scitranslmed.3008669. Accessed 22 Oct 2026.
  2. peer reviewed paper
    Restoring natural sensory feedback in real-time bidirectional hand prostheses
    Stanisa Raspopovic, Marco Capogrosso, Francesco Maria Petrini et al.. Science Translational Medicine, Feb 2014. DOI: 10.1126/scitranslmed.3006820. Accessed 22 Oct 2026.
  3. peer reviewed paper
    Restoration of motor control and proprioceptive and cutaneous sensation in humans with prior upper-limb amputation via multiple Utah Slanted Electrode Arrays (USEAs) implanted in residual peripheral arm nerves
    Suzanne Wendelken, David M. Page, Tyler Davis et al.. Journal of NeuroEngineering and Rehabilitation, 25 Nov 2017. DOI: 10.1186/s12984-017-0320-4. Accessed 22 Oct 2026.
  4. peer reviewed paper
    Discriminability of multiple cutaneous and proprioceptive hand percepts evoked by intraneural stimulation with Utah slanted electrode arrays in human amputees
    David M. Page, Jacob A. George, Suzanne M. Wendelken et al.. Journal of NeuroEngineering and Rehabilitation, 21 Jan 2021. DOI: 10.1186/s12984-021-00808-4. Accessed 22 Oct 2026.
  5. peer reviewed paper
    A regenerative peripheral nerve interface allows real-time control of an artificial hand in upper limb amputees
    Philip P. Vu, Alex K. Vaskov, Zachary T. Irwin et al.. Science Translational Medicine, Mar 2020. DOI: 10.1126/scitranslmed.aay2857. Accessed 22 Oct 2026.
  6. review article
    Merging Humans and Neuroprosthetics through Regenerative Peripheral Nerve Interfaces
    Yucheng Tian, Alex K Vaskov, Widya Adidharma et al.. Seminars in Plastic Surgery, 6 Feb 2024. DOI: 10.1055/s-0044-1779028. Accessed 22 Oct 2026.
  7. peer reviewed paper
    Regenerative peripheral nerve interfaces (RPNIs) and implanted electrodes improve online control of prostheses for hand and wrist
    Dylan M. Wallace, Luis Hernan Cubillos, Mira E. Mutnick et al.. Journal of Neural Engineering, 5 Feb 2026. DOI: 10.1088/1741-2552/ae36d2. Accessed 22 Oct 2026.

Revision history

3 changes since this profile was created.

Changes on 22 Oct 2026
Published on owner instruction (loop iteration, research batch 002 and category gaps, 2026-10-22)80cd179
Sources and claims re-checked against originals409337d
Initial profile drafted from primary sourceseaac9eb