Trial Outcomes & Findings for Spinal Cord Stimulation for Restoration of Function in Lower-Limb Amputees, 90-Day (NCT NCT04547582)

Results Overview

Investigators will track the number of participants experiencing serious device-related adverse events, such as unresolved superficial infection resulting in lead removal, deep infection, inpatient hospitalization, withdrawal from the study due to worsening pain or intolerable dysesthesia, or fracture due to falls related to the study interventions, that occur during the course of and up to 90 days following implantation.

Recruitment status

TERMINATED

Study phase

NA

Target enrollment

4 participants

Primary outcome timeframe

90 days

Results posted on

2026-01-07

Participant Flow

Subjects were enrolled from 2021 to 2023 from affiliated amputee clinics. Recruitment continued through 2025, but no additional subjects were enrolled.

Enrollment is defined as completing informed consent.

Participant milestones

Participant milestones
Measure	Spinal Cord Stimulation Spinal cord stimulator leads (2-3 leads) will be placed in the lumbar epidural space of lower limb amputees to determine if the patient experiences any pain reduction from spinal cord stimulation. Participants in this study receive spinal cord stimulation will be trans-tibial amputees that are at least six month post--amputation. Subjects will have varying levels of phantom limb sensation and pain, but should have no other significant neurological disorders. Spinal cord stimulator: Spinal cord stimulator leads (2-3 leads) will be placed in the lumbar epidural space of lower limb amputees to determine if the patient experiences any pain reduction from spinal cord stimulation.
Overall Study STARTED	1
Overall Study COMPLETED	1
Overall Study NOT COMPLETED	0

Reasons for withdrawal

Withdrawal data not reported

Baseline Characteristics

Spinal Cord Stimulation for Restoration of Function in Lower-Limb Amputees, 90-Day

Baseline characteristics by cohort

Baseline characteristics by cohort
Measure	Spinal Cord Stimulation n=1 Participants Spinal cord stimulator leads (2-3 leads) will be placed in the lumbar epidural space of lower limb amputees to determine if the patient experiences any pain reduction from spinal cord stimulation. Participants in this study receive spinal cord stimulation will be trans-tibial amputees that are at least six month post--amputation. Subjects will have varying levels of phantom limb sensation and pain, but should have no other significant neurological disorders. Spinal cord stimulator: Spinal cord stimulator leads (2-3 leads) will be placed in the lumbar epidural space of lower limb amputees to determine if the patient experiences any pain reduction from spinal cord stimulation.
Age, Categorical <=18 years	0 Participants n=37 Participants
Age, Categorical Between 18 and 65 years	1 Participants n=37 Participants
Age, Categorical >=65 years	0 Participants n=37 Participants
Sex: Female, Male Female	1 Participants n=37 Participants
Sex: Female, Male Male	0 Participants n=37 Participants
Race (NIH/OMB) American Indian or Alaska Native	0 Participants n=37 Participants
Race (NIH/OMB) Asian	0 Participants n=37 Participants
Race (NIH/OMB) Native Hawaiian or Other Pacific Islander	0 Participants n=37 Participants
Race (NIH/OMB) Black or African American	0 Participants n=37 Participants
Race (NIH/OMB) White	1 Participants n=37 Participants
Race (NIH/OMB) More than one race	0 Participants n=37 Participants
Race (NIH/OMB) Unknown or Not Reported	0 Participants n=37 Participants
Region of Enrollment United States	1 participants n=37 Participants

PRIMARY outcome

Timeframe: 90 days

Population: One participant was implanted with spinal cord stimulation leads.

Investigators will track the number of participants experiencing serious device-related adverse events, such as unresolved superficial infection resulting in lead removal, deep infection, inpatient hospitalization, withdrawal from the study due to worsening pain or intolerable dysesthesia, or fracture due to falls related to the study interventions, that occur during the course of and up to 90 days following implantation.

Outcome measures

Outcome measures
Measure	Spinal cord stimulation n=1 Participants Spinal cord stimulator leads (2-3 leads) will be placed in the lumbar epidural space of lower limb amputees to determine if the patient experiences any pain reduction from spinal cord stimulation. Participants in this study receive spinal cord stimulation will be trans-tibial amputees that are at least six month post--amputation. Subjects will have varying levels of phantom limb sensation and pain, but should have no other significant neurological disorders. Spinal cord stimulator: Spinal cord stimulator leads (2-3 leads) will be placed in the lumbar epidural space of lower limb amputees to determine if the patient experiences any pain reduction from spinal cord stimulation.
Number of Participants Experiencing Serious Device-related Adverse Events up to 90 Days Following Implantation	0 Participants

PRIMARY outcome

Timeframe: 90 days

Quantify the threshold stimulus required to evoke sensory percepts during epidural spinal nerve stimulation.

Outcome measures

Outcome measures
Measure	Spinal cord stimulation n=1 Participants Spinal cord stimulator leads (2-3 leads) will be placed in the lumbar epidural space of lower limb amputees to determine if the patient experiences any pain reduction from spinal cord stimulation. Participants in this study receive spinal cord stimulation will be trans-tibial amputees that are at least six month post--amputation. Subjects will have varying levels of phantom limb sensation and pain, but should have no other significant neurological disorders. Spinal cord stimulator: Spinal cord stimulator leads (2-3 leads) will be placed in the lumbar epidural space of lower limb amputees to determine if the patient experiences any pain reduction from spinal cord stimulation.
Minimum Amplitude of Pulse Required to Evoke Sensory Percepts	2 milliamps

PRIMARY outcome

Timeframe: 90 days

Quantify the threshold (minimum charge) stimulus required to evoke neurophysiological responses during epidural spinal nerve stimulation

Outcome measures

Outcome measures
Measure	Spinal cord stimulation n=1 Participants Spinal cord stimulator leads (2-3 leads) will be placed in the lumbar epidural space of lower limb amputees to determine if the patient experiences any pain reduction from spinal cord stimulation. Participants in this study receive spinal cord stimulation will be trans-tibial amputees that are at least six month post--amputation. Subjects will have varying levels of phantom limb sensation and pain, but should have no other significant neurological disorders. Spinal cord stimulator: Spinal cord stimulator leads (2-3 leads) will be placed in the lumbar epidural space of lower limb amputees to determine if the patient experiences any pain reduction from spinal cord stimulation.
Minimum Charge Required to Evoke a Neurophysiological Response	1.23 uC (microcoulombs)

PRIMARY outcome

Timeframe: 90 days

Participants reporting sensation on missing toes from spinal cord stimulation.

Outcome measures

Outcome measures
Measure	Spinal cord stimulation n=1 Participants Spinal cord stimulator leads (2-3 leads) will be placed in the lumbar epidural space of lower limb amputees to determine if the patient experiences any pain reduction from spinal cord stimulation. Participants in this study receive spinal cord stimulation will be trans-tibial amputees that are at least six month post--amputation. Subjects will have varying levels of phantom limb sensation and pain, but should have no other significant neurological disorders. Spinal cord stimulator: Spinal cord stimulator leads (2-3 leads) will be placed in the lumbar epidural space of lower limb amputees to determine if the patient experiences any pain reduction from spinal cord stimulation.
Location of Evoked Sensation - Missing Toes	1 Participants

PRIMARY outcome

Timeframe: 90 days

Participants perceiving sensation on the plantar surface of missing foot

Outcome measures

Outcome measures
Measure	Spinal cord stimulation n=1 Participants Spinal cord stimulator leads (2-3 leads) will be placed in the lumbar epidural space of lower limb amputees to determine if the patient experiences any pain reduction from spinal cord stimulation. Participants in this study receive spinal cord stimulation will be trans-tibial amputees that are at least six month post--amputation. Subjects will have varying levels of phantom limb sensation and pain, but should have no other significant neurological disorders. Spinal cord stimulator: Spinal cord stimulator leads (2-3 leads) will be placed in the lumbar epidural space of lower limb amputees to determine if the patient experiences any pain reduction from spinal cord stimulation.
Location of Evoked Sensation - Plantar Surface of Missing Foot	1 Participants

SECONDARY outcome

Timeframe: Pre-implant (baseline), Weeks 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, and post-explant (90 days)

The McGill Pain Questionnaire is a questionnaire used to evaluate the severity of pain experienced by the participant. The questionnaire is scaled, with a minimum and maximum pain score of 0 and 78, respectively. The higher the score on the questionnaire, the more intense the pain felt by the participant. A lower score than previously reported represents a decrease in experienced phantom limb pain. Before placement of the spinal cord stimulator leads, investigators will document the subject's description of their history of perceived phantom limb. Investigators will ask them to periodically update their perception of the limb throughout experimental sessions, as well as within a month after the device has been removed.

Outcome measures

Outcome measures
Measure	Spinal cord stimulation n=1 Participants Spinal cord stimulator leads (2-3 leads) will be placed in the lumbar epidural space of lower limb amputees to determine if the patient experiences any pain reduction from spinal cord stimulation. Participants in this study receive spinal cord stimulation will be trans-tibial amputees that are at least six month post--amputation. Subjects will have varying levels of phantom limb sensation and pain, but should have no other significant neurological disorders. Spinal cord stimulator: Spinal cord stimulator leads (2-3 leads) will be placed in the lumbar epidural space of lower limb amputees to determine if the patient experiences any pain reduction from spinal cord stimulation.
Change in Phantom Limb Pain Using the McGill Pain Questionnaire Pre-implant (baseline)	48 score on a scale
Change in Phantom Limb Pain Using the McGill Pain Questionnaire Week 1 (after implant)	32 score on a scale
Change in Phantom Limb Pain Using the McGill Pain Questionnaire Week 2	45 score on a scale
Change in Phantom Limb Pain Using the McGill Pain Questionnaire Week 3	45 score on a scale
Change in Phantom Limb Pain Using the McGill Pain Questionnaire Week 4	23 score on a scale
Change in Phantom Limb Pain Using the McGill Pain Questionnaire Week 5	38 score on a scale
Change in Phantom Limb Pain Using the McGill Pain Questionnaire Week 6	32 score on a scale
Change in Phantom Limb Pain Using the McGill Pain Questionnaire Week 7	34 score on a scale
Change in Phantom Limb Pain Using the McGill Pain Questionnaire Week 8	17 score on a scale
Change in Phantom Limb Pain Using the McGill Pain Questionnaire Week 9	46 score on a scale
Change in Phantom Limb Pain Using the McGill Pain Questionnaire Week 10	41 score on a scale
Change in Phantom Limb Pain Using the McGill Pain Questionnaire Week 11	65 score on a scale
Change in Phantom Limb Pain Using the McGill Pain Questionnaire Post-explant (90 days)	47 score on a scale

SECONDARY outcome

Timeframe: 90 days

Population: For all reported sensations, each electrode was stimulated with a 1-second long pulse train.

Document the subjective perception of lumbosacral epidural spinal nerve stimulation for restoration of sensation. The investigators will ask each subject to provide subjective feedback on their perceived utility of the sensory feedback provided by the device. A total of 13 natural descriptors and 5 paresthetic descriptors were presented to participants weekly to describe the sensation provided via spinal cord stimulation. The goal of the study is to elicit more natural than paresthetic descriptors from participants. Natural: pressure, tickle, flutter, warm, sharp, prick, cool, pulsing, vibration, itch, urge to move, touch, tap Parethetic: buzz, tingle, shock, electric current, numb

Outcome measures

Outcome measures
Measure	Spinal cord stimulation n=1 Participants Spinal cord stimulator leads (2-3 leads) will be placed in the lumbar epidural space of lower limb amputees to determine if the patient experiences any pain reduction from spinal cord stimulation. Participants in this study receive spinal cord stimulation will be trans-tibial amputees that are at least six month post--amputation. Subjects will have varying levels of phantom limb sensation and pain, but should have no other significant neurological disorders. Spinal cord stimulator: Spinal cord stimulator leads (2-3 leads) will be placed in the lumbar epidural space of lower limb amputees to determine if the patient experiences any pain reduction from spinal cord stimulation.
Qualitative Self-report of Evoked Sensations More natural than paresthetic descriptors.	1 Participants
Qualitative Self-report of Evoked Sensations More paresthetic than natural descriptors.	0 Participants

SECONDARY outcome

Timeframe: 90 days

Population: Individuals implanted with spinal cord stimulator leads in lumbar spine

Investigators will test the subject's success rate during control of prosthetic limb with and without sensory feedback provided by electrical stimulation of the spinal roots. Using either a virtual prosthetic limb or an instrumented prosthesis, stimulation of the spinal roots will be modulated based on signals recorded from the limb.

Outcome measures

Outcome measures
Measure	Spinal cord stimulation n=1 Participants Spinal cord stimulator leads (2-3 leads) will be placed in the lumbar epidural space of lower limb amputees to determine if the patient experiences any pain reduction from spinal cord stimulation. Participants in this study receive spinal cord stimulation will be trans-tibial amputees that are at least six month post--amputation. Subjects will have varying levels of phantom limb sensation and pain, but should have no other significant neurological disorders. Spinal cord stimulator: Spinal cord stimulator leads (2-3 leads) will be placed in the lumbar epidural space of lower limb amputees to determine if the patient experiences any pain reduction from spinal cord stimulation.
Able to Use a Prosthetic Limb With Neural Signals	1 Participants

Adverse Events

Spinal Cord Stimulation

Serious events: 0 serious events

Other events: 1 other events

Deaths: 0 deaths

Serious adverse events

Adverse event data not reported

Other adverse events

Other adverse events
Measure	Spinal Cord Stimulation n=1 participants at risk Spinal cord stimulator leads (2-3 leads) will be placed in the lumbar epidural space of lower limb amputees to determine if the patient experiences any pain reduction from spinal cord stimulation. Participants in this study receive spinal cord stimulation will be trans-tibial amputees that are at least six month post--amputation. Subjects will have varying levels of phantom limb sensation and pain, but should have no other significant neurological disorders. Spinal cord stimulator: Spinal cord stimulator leads (2-3 leads) will be placed in the lumbar epidural space of lower limb amputees to determine if the patient experiences any pain reduction from spinal cord stimulation.
Surgical and medical procedures Incision pain	100.0% 1/1 • Number of events 1 • 90 days Self-report by participant
Surgical and medical procedures Chest pain after surgery	100.0% 1/1 • Number of events 1 • 90 days Self-report by participant

Additional Information

Dr. Lee Fisher, PhD

University of Pittsburgh

Phone: 412-383-1326

Email: [email protected]

Results disclosure agreements

Principal investigator is a sponsor employee
Publication restrictions are in place