Lower Extremity AmputeeNCT04658693
Functional and Neuroprotective Effects of Restoring Lower Limb Sensation After Diabetic Peripheral Neuropathy
A study testing Implanted Multi contact stimulating electrode and intramuscular electromyography recording electrode in people with Lower Extremity Amputee and Diabetic Peripheral Neuropathy, run by VA Office of Research and Development at 1 site in United States.
Trial summary
The purpose of this study is to evaluate the effectiveness of providing sensation of the missing limb to individuals with above and below the knee limb loss. The investigators will implant stimulating electrodes to send small electrical currents to the remaining nerves. Read more about this study
- Who is it for?
- Ages 18 years and older
- Conditions the study is for
- Lower Extremity Amputee, Diabetic Peripheral Neuropathy
- What is being tested?
- Implanted Multi contact stimulating electrode and intramuscular electromyography recording electrode
- Type of treatment
- Injection or infusion, Medical device
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 15 participants
- Where
- 1 siteUnited States
- Study dates
- 2 Mar 2021to 1 Oct 2027
- Phase
- Interventional
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 years and older
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- Veteran
- Chronic, medically stable lower limb amputation due to diabetes or insensate foot due to Diabetic peripheral neuropathy
- Being ambulatory and ability to stand or walk with prosthesis or orthosis
- Viable target nerves in the lower extremity as determined by standard-of-care clinical tests of nerve conduction, response to stimulation, sensory evoked potentials (SEP) and the like
- Good skin integrity and personal hygiene
- Absence of autoimmune deficiencies, seizure disorders or cardiac abnormalities contraindicating stimulation
- Sufficient social support and personal ability to tolerate study procedures and comply with follow-up schedule
Who cannot join
- Active pressure ulcers or chronic skin ulcerations
- Uncontrolled diabetes with HbA1c greater than or equal to 69 mmol/mol (8.5%)
- Significant vascular disease
- Significant history of poor wound healing
- Significant history of uncontrolled infections
- Active infection
Show all 14Show fewer
- Significant pain in the foot, residual or phantom limb
- Pregnancy
- Inability to speak English: The study design requires the subject to communicate and describe the elicited sensations in their lower limb
- History of vestibular or movement disorders that would compromise balance or walking
- Class II or III obesity (Body Mass Index > 35)
- Uncontrolled depression, psychoses or cognitive impairments. Subjects with unstable mental illness or severe cognitive impairments may be unable to comply with a long term study schedule
- Expectation that magnetic resonance imaging (MRI) will be required at any point for the duration of study or while percutaneous leads are in place. At this time MRI is contraindicated, subjects who require regular MRI should not enroll
- Arthritis in the area of implant- Inflammation or stiffness in the area of implant could limit placement of the electrodes
Trial locations and contacts
1 site in 1 country.
United States1 site
Louis Stokes VA Medical Center, Cleveland, OH
Cleveland, Ohio, 44106-1702
About this study
The purpose of this study is to evaluate the effectiveness of providing sensation of the missing limb to individuals with above and below the knee limb loss. The investigators will implant stimulating electrodes to send small electrical currents to the remaining nerves. These small electrical currents cause the nerves to generate signals that are then transferred to your brain similar to how the information about your foot and lower limb used to be transferred to the brain prior to your limb loss. Additionally, there is the option to have muscle recording electrodes implanted within the muscles of the lower limb with the goal to develop a motor controller that would allow the user to have intuitive control of a robotic prosthetic leg.
Read the detailed description
Electrodes are surgically implanted on one to four nerves of the residual limb. Intramuscular recording electrodes can be implanted in the lower limbs and hip muscles in order to obtain electromyography (EMG) signals. The EMG recordings will be used to develop an algorithm which can operate an advanced robotic prosthesis in which the prosthesis joint(s) movements could be controlled. An external wearable stimulation device controls the delivery of electrical pulses to the implanted system. An instrumented prosthesis will be developed such that perceived sensations would correspond to prosthesis interactions with the floor. The instrumented prosthesis will be worn while the participant is engaging in various functional tasks, such as standing, walking or climbing stairs or with visual or mental distractions.
- Being tested
- Implanted Multi contact stimulating electrode and intramuscular electromyography recording electrode
- Keywords
- Sensory Feedback, Limb Loss, Prosthesis User
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Implanted Multi contact stimulating electrode and intramuscular electromyography recording electrodeDevice
Also called Sensory Neuroprosthesis
See arm description
| Study group | Role | What they receive |
|---|---|---|
| Multi contact electrode implant and implanted electromyography recording electrodes | Experimental | Fifteen subjects with lower limb amputation will receive implanted multicontact stimulating nerve cuff electrodes connected to temporary percutaneous leads.
During experimental testing, a small amount of stimulation will be applied to the nerves through the contacts of the multichannel cuff electrode. Receives: Device: Implanted Multi contact stimulating electrode and intramuscular electromyography recording electrode |
What is being measured
The primary outcome is the main question the study is designed to answer.
Stimulation thresholds
Quantify the minimum stimulation required to evoke electrically induced sensations on the phantom limb.
Measured: 9 months post implant
Functional Gait Assessment (FGA)
The Functional Gait Assessment is a 10 task test that measures postural stability. Each task is scored from 0 -3 with 0 indicating severe impairment in the task and 3 indicating normal ambulation. The scores are combined to give a total score. The maximum score is 30. A higher score indicates a better outcome.
Measured: 6 months post implant
Secondary outcomes (1)
Neuropathic Pain Syndrome Inventory (NPSI)
The NPSI is comprised of five subscales, each representing different dimensions of neuropathic pain: burning spontaneous pain (burning), pressing spontaneous pain (pressing), paroxysmal pain (paroxysmal), evoked pain (evoked), and paresthesia/dysesthesia Each area subscale is scored between 0-10. The scores are not combined, but are able to report on different aspects of neuropathic pain. A higher score indicates a worse outcome.
Measured: 4 years post implant
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted8 Dec 2020
- Study start2 Mar 2021
- Primary completion1 Oct 2027 (estimated)
- Study completion1 Oct 2027 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Lower Extremity AmputeeStudies of the same condition, open and under way.
- More trials run by VA Office of Research and DevelopmentThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Device feasibility
- Allocation
- Not applicable
- Intervention model
- Single group
- Model description
- The project will take the form of a series of controlled single-subject feasibility and proof-of-concept studies with repeated measures. Subjects will act as their own concurrent controls with and without sensory stimulation, as well as their own longitudinal (historical) controls pre- and post-implementation of the Sensory Neuroprosthesis.
- Masking
- None (open label)
- Enrolment
- 15 participants (actual)
Sponsor and investigators
- Lead sponsor
- VA Office of Research and Development
- Sponsor type
- US federal agency
- Responsible party
- Sponsor
- Investigators
- Ronald Triolo, PhD, Principal investigator, Louis Stokes VA Medical Center, Cleveland, OH
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT04658693
- Sponsor's protocol ID
- A3566-R
- Other IDs
- 5I01RX003566-05, 1583890
- Status last verified
- Oct 2026
- First submitted
- 20 Nov 2020
- Last updated
- 23 Oct 2026
- Results posted
- No
- Data monitoring committee
- Yes
- FDA-regulated drug
- No
- FDA-regulated device
- Yes
- Individual data sharing
- No: Deidentified data will be provided upon request.
Study at a glance
From the registry record, last updated by the sponsor on 23 Oct 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Functional and Neuroprotective Effects of Restoring Lower Limb Sensation After Diabetic Peripheral Neuropathy
- ClinicalTrials.gov ID
- NCT04658693
- Acronym / sponsor ID
- A3566-R
- Keywords
- Sensory Feedback, Limb Loss, Prosthesis User
- Study type
- Interventional
- Recruitment status
- Active, not recruiting
- Enrolment
- 15 participants (actual)
- Lead sponsor
- VA Office of Research and DevelopmentUS federal agency
- Study start
- 2 Mar 2021 (actual)
- Primary completion
- 1 Oct 2027 (estimated)
- Study completion
- 1 Oct 2027 (estimated)
- First posted
- 8 Dec 2020 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
The purpose of this study is to evaluate the effectiveness of providing sensation of the missing limb to individuals with above and below the knee limb loss. The investigators will implant stimulating electrodes to send small electrical currents to the remaining nerves. These small electrical currents cause the nerves to generate signals that are then transferred to your brain similar to how the information about your foot and lower limb used to be transferred to the brain prior to your limb loss. Additionally, there is the option to have muscle recording electrodes implanted within the muscles of the lower limb with the goal to develop a motor controller that would allow the user to have intuitive control of a robotic prosthetic leg.
Detailed description
Electrodes are surgically implanted on one to four nerves of the residual limb. Intramuscular recording electrodes can be implanted in the lower limbs and hip muscles in order to obtain electromyography (EMG) signals. The EMG recordings will be used to develop an algorithm which can operate an advanced robotic prosthesis in which the prosthesis joint(s) movements could be controlled. An external wearable stimulation device controls the delivery of electrical pulses to the implanted system. An instrumented prosthesis will be developed such that perceived sensations would correspond to prosthesis interactions with the floor. The instrumented prosthesis will be worn while the participant is engaging in various functional tasks, such as standing, walking or climbing stairs or with visual or mental distractions.
Study design
- Primary purpose
- Device feasibility
- Allocation
- Not applicable
- Intervention model
- Single group
- Masking
- None (open label)
- Number of arms
- 1
- Model description
- The project will take the form of a series of controlled single-subject feasibility and proof-of-concept studies with repeated measures. Subjects will act as their own concurrent controls with and without sensory stimulation, as well as their own longitudinal (historical) controls pre- and post-implementation of the Sensory Neuroprosthesis.
| Arm | Type | Receives |
|---|---|---|
| Multi contact electrode implant and implanted electromyography recording electrodes | Experimental | Device: Implanted Multi contact stimulating electrode and intramuscular electromyography recording electrodeFifteen subjects with lower limb amputation will receive implanted multicontact stimulating nerve cuff electrodes connected to temporary percutaneous leads. During experimental testing, a small amount of stimulation will be applied to the nerves through the contacts of the multichannel cuff electrode. |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (7 listed)
- Veteran
- Chronic, medically stable lower limb amputation due to diabetes or insensate foot due to Diabetic peripheral neuropathy
- Being ambulatory and ability to stand or walk with prosthesis or orthosis
- Viable target nerves in the lower extremity as determined by standard-of-care clinical tests of nerve conduction, response to stimulation, sensory evoked potentials (SEP) and the like
- Good skin integrity and personal hygiene
Key exclusion criteria (14 listed)
- Active pressure ulcers or chronic skin ulcerations
- Uncontrolled diabetes with HbA1c greater than or equal to 69 mmol/mol (8.5%)
- Significant vascular disease
- Significant history of poor wound healing
- Significant history of uncontrolled infections
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Implanted Multi contact stimulating electrode and intramuscular electromyography recording electrodeAlso: Sensory NeuroprosthesisSee arm description | Device | Multi contact electrode implant and implanted electromyography recording electrodes |
Primary outcome
Stimulation thresholds
Time frame: 9 months post implant
Quantify the minimum stimulation required to evoke electrically induced sensations on the phantom limb.
Functional Gait Assessment (FGA)
Time frame: 6 months post implant
The Functional Gait Assessment is a 10 task test that measures postural stability. Each task is scored from 0 -3 with 0 indicating severe impairment in the task and 3 indicating normal ambulation. The scores are combined to give a total score. The maximum score is 30. A higher score indicates a better outcome.
1 secondary outcome
Neuropathic Pain Syndrome Inventory (NPSI)
Time frame: 4 years post implant
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 23 Oct 2026.
- VA Center of Excellence website listing this and other ongoing studies.Link provided by the sponsor.
- Individual participant dataSharing planned: No. Deidentified data will be provided upon request.
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
Ronald Triolo, PhD principal investigator
Louis Stokes VA Medical Center, Cleveland, OH
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Implanted Multi contact stimulating electrode and intramuscular electromyography recording electrode in people with Lower Extremity Amputee and Diabetic Peripheral Neuropathy, run by VA Office of Research and Development at 1 site in United States.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 7 inclusion and 14 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: under way, not looking for participants, as of the sponsor's last update on 23 Oct 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in United States. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Stimulation thresholds (time frame: 9 months post implant). The study lists 2 primary outcomes in all. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 23 Oct 2026.