6 Participants Needed

Neural Interface for Upper Limb Amputation

(PSI Trial)

EL
AN
MS
Overseen ByMelissa S Schmitt
Age: 18+
Sex: Any
Trial Phase: Academic
Sponsor: VA Office of Research and Development
No Placebo GroupAll trial participants will receive the active study treatment (no placebo)

Trial Summary

What is the purpose of this trial?

The purpose of this study is to characterize proprioceptive sensations in the missing limb of upper limb amputees using nerve stimulation, and to develop advanced controllers for moving a prosthesis. Proprioceptive sensations are the sensations that tell individuals where their hand is in space, and if it is moving. The research team uses Functional Electrical Stimulation (FES), which involves applying small electric currents to the nerves. These signals are then transferred to the brain just like the information about the individual's intact hand used to be transferred to their brain. This study will test different placements for stimulation and determine which one(s) provide the individual with proprioceptive sensations. The investigators want to know what the participants feel and if the investigators can use proprioceptive sensation to give the participants information about limb movement and position.

Will I have to stop taking my current medications?

The trial information does not specify whether you need to stop taking your current medications. It's best to discuss this with the study team to get a clear answer.

What data supports the effectiveness of the treatment Chronically Implanted Neural and Muscular Interface for upper limb amputation?

Research shows that the Regenerative Peripheral Nerve Interface (RPNI) and implanted electrodes provide reliable and consistent signals for controlling prosthetic limbs over long periods, with one study demonstrating over 94% accuracy in real-time prosthetic performance for more than 600 days. Additionally, the use of targeted muscle reinnervation (TMR) and chronically implanted sensors has shown substantial functional improvements in controlling robotic arms for above-elbow amputees.12345

Is the neural interface for upper limb amputation safe for humans?

Research on neural interfaces, including those for prosthetic control, shows that implanted electrodes can provide reliable and stable control over long periods, with some studies demonstrating successful use for over a year. Animal studies also support the long-term biocompatibility of these interfaces, suggesting they are generally safe for human use.14678

How is the Chronically Implanted Neural and Muscular Interface treatment different from other treatments for upper limb amputation?

This treatment is unique because it involves chronically implanted electrodes that provide stable and reliable control of prosthetic limbs by directly interfacing with nerves and muscles, allowing for more natural and intuitive movement compared to traditional surface electrodes.145910

Research Team

EL

Emily L Graczyk, PhD

Principal Investigator

Louis Stokes VA Medical Center, Cleveland, OH

Eligibility Criteria

This trial is for individuals with a single upper limb amputation who are medically fit for anesthesia, have been using a prosthesis fitted by a specialist for at least one month, and can follow the study protocol. They must have good nerve function in the remaining limb and be mentally competent to participate. Pregnant women or those not preventing pregnancy, non-English speakers, people unfit for surgery, with uncontrolled diabetes or severe pain that interferes with activities are excluded.

Inclusion Criteria

Willingness and availability to follow the study protocol
A psychologist has confirmed I'm mentally fit for the study.
My remaining limb has working nerves.
See 4 more

Exclusion Criteria

I am not healthy enough for surgery.
Inability to speak English
I am able to understand and agree to the study's requirements.
See 6 more

Timeline

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

Implantation and Initial Testing

Participants are implanted with neural and muscular interfaces and undergo initial testing to characterize proprioceptive sensations using Functional Electrical Stimulation (FES).

4-8 weeks

Proprioceptive Sensation Characterization

Characterization of proprioceptive sensations elicited by peripheral nerve stimulation, including testing of time-varying Peripheral Nerve Stimulation (PNS) patterns and paired agonist-antagonist stimulation strategies.

6 months
Monthly visits for assessments

Mechanisms Investigation

Investigation of the mechanisms of stimulation-evoked proprioception, including motor block tests and Targeted Muscle Reinnervation.

6 months
Monthly visits for assessments

Integration with Motor Control

Integration of proprioceptive stimulation with motor control during posture matching tasks, including virtual reality tasks and psychometric dissimilarity rating tasks.

12 months
Monthly visits for assessments

Follow-up

Participants are monitored for safety and effectiveness after the main intervention phases.

6 months

Treatment Details

Interventions

  • Chronically Implanted Neural and Muscular Interface
Trial OverviewThe study aims to create sensations of hand position and movement (proprioception) in amputees by stimulating nerves through Functional Electrical Stimulation (FES). It will test different stimulation placements to evoke proprioceptive sensations and develop advanced prosthetic controllers based on these findings.
Participant Groups
1Treatment groups
Experimental Treatment
Group I: Chronically Implanted Neural and Muscular InterfaceExperimental Treatment1 Intervention
6 eligible participants will be chronically implanted with neural and muscular interfaces to characterize proprioceptive sensations using Functional Electrical Stimulation (FES).

Find a Clinic Near You

Who Is Running the Clinical Trial?

VA Office of Research and Development

Lead Sponsor

Trials
1,691
Recruited
3,759,000+

Findings from Research

The Regenerative Peripheral Nerve Interface (RPNI) provides reliable and consistent signals for upper-limb neuroprosthetic control, maintaining a high signal-to-noise ratio for up to 1054 days in participants.
One participant achieved over 94% accuracy in real-time prosthetic performance for 604 days and completed complex tasks with 99% accuracy for 611 days, demonstrating the long-term efficacy of RPNIs in controlling prosthetic devices.
Long-term upper-extremity prosthetic control using regenerative peripheral nerve interfaces and implanted EMG electrodes.Vu, PP., Vaskov, AK., Lee, C., et al.[2023]
The novel Regenerative Peripheral Nerve Interface (RPNI) demonstrated reliable signal generation from a residual nerve after a 14-month maturation period, indicating its potential for effective control of neuroprosthetic limbs.
Electromyographic signals from the RPNI were consistent and strong, exceeding 4 mV, with no signs of muscle denervation or significant tissue damage, suggesting long-term viability and safety for patients.
Electrically stimulated signals from a long-term Regenerative Peripheral Nerve Interface.Langhals, NB., Woo, SL., Moon, JD., et al.[2020]
The agonist-antagonist myoneural interface (AMI) allows for improved control and feedback from prosthetic devices by preserving natural muscle dynamics, enabling bidirectional communication between the muscles and the central nervous system.
This study introduces a dual-stage surgical procedure to implement AMIs in patients with traumatic or previous amputations, showing that the AMI maintains robust physiological function and can integrate into the body's reflexive systems.
Towards functional restoration for persons with limb amputation: A dual-stage implementation of regenerative agonist-antagonist myoneural interfaces.Srinivasan, SS., Diaz, M., Carty, M., et al.[2023]

References

Long-term upper-extremity prosthetic control using regenerative peripheral nerve interfaces and implanted EMG electrodes. [2023]
Electrically stimulated signals from a long-term Regenerative Peripheral Nerve Interface. [2020]
Towards functional restoration for persons with limb amputation: A dual-stage implementation of regenerative agonist-antagonist myoneural interfaces. [2023]
An osseointegrated human-machine gateway for long-term sensory feedback and motor control of artificial limbs. [2021]
Long-term implant of intramuscular sensors and nerve transfers for wireless control of robotic arms in above-elbow amputees. [2021]
Neural Prosthetics:A Review of Empirical vs. Systems Engineering Strategies. [2023]
The Agonist-Antagonist Myoneural Interface. [2022]
Experimental Testing of Bionic Peripheral Nerve and Muscle Interfaces: Animal Model Considerations. [2020]
A critical review of interfaces with the peripheral nervous system for the control of neuroprostheses and hybrid bionic systems. [2006]
10.United Statespubmed.ncbi.nlm.nih.gov
Neural interfaces for control of upper limb prostheses: the state of the art and future possibilities. [2011]