An interventional study of Boston Scientific Stimulator Lead in Phantom Limb, sponsored by Lee Fisher, PhD. Completed at 1 site in United States. Open to participants aged 18 Years to 70 Years. Per ClinicalTrials.gov, last updated 2025-10-08.
Sponsored by Lee Fisher, PhD · Not applicable, Interventional, and Treatment
Individuals with upper-limb amputation usually have intact nerves within the residual limb, and studies have demonstrated that electrical stimulation of those nerves can produce sensations that appear to emanate from the amputated limb. In this study, investigators will examine the sensations that are produced by electrical stimulation of these nerves at the location where they exit the spinal cord. Stimulation of the spinal cord is commonly used to treat intractable back and limb pain, and the procedure includes a test phase in which electrodes are temporarily placed under the skin near the spinal cord and removed at the end of testing. Similarly, in this study, electrodes will be placed near the spinal cord in the upper back and neck, and stimulation will be applied over the course of multiple testing sessions, lasting less than 30 days. The electrodes will be removed at the last day of testing. During each testing session, electrical stimulation will be applied through the electrodes and a series of tests will be performed to determine the types of sensations produced by stimulation. In addition to producing meaningful sensations with electrical stimulation, this study will also test the effect of stimulation on phantom limb sensations and phantom limb pain.
The purpose of this research study is to characterize the types of sensations that can be produced by stimulating the spinal nerves in upper-limb amputees, as well as the effects of that stimulation on phantom limb pain. The study involves a medical procedure to temporarily place one to three stimulation electrodes in the space near the spinal cord. This medical procedure will be performed under local anesthesia, and will take approximately one to two hours. Afterwards, the electrodes will be connected to an external stimulator and a series of experiments will be performed to characterize the types of sensations generated by electrical stimulation of the spinal cord and spinal nerves, as well as to measure the effect of stimulation on phantom limb sensations and phantom limb pain. Over the course of less than 30 days, there will be up to 20 of these experimental sessions. At the end of the final experimental session, the stimulation electrodes will be removed by gently pulling on them.
The investigators are inviting participants to consider participating in this research because they have an upper-limb amputation. Participants must be between the ages of 18 and 70 and at least one year post-amputation. Participants must be willing to travel to the University of Pittsburgh at least twice per week for 30 days.
Participants cannot have any serious diseases or disorders that affect your ability to participate in this study. Women who are pregnant or plan to become pregnant during the study cannot be included. The investigators will ask females of child-bearing potential to undergo a urine pregnancy test prior to any procedures (such as MRI, x-ray, fluoroscopy) that may disrupt the healthy development of an unborn child. If participants are currently taking any medications that thin their blood, participants will not be eligible for this study. Participants will have to meet other criteria to be eligible, which will be reviewed with participants upon their consent. The investigators will screen up to 15 people and expect that up to 10 individuals will complete this study.
Exclusion Criteria:
A Boston Scientific Stimulator Lead (PMA P030017) will be placed in the cervical epidural space of ten upper-limb amputees and steered laterally towards the dorsal spinal roots under fluoroscopic guidance.
Device: Boston Scientific Stimulator Lead
A Boston Scientific (PMA P030017) spinal cord stimulator lead will be placed in the cervical epidural space of ten upper-limb amputees and steered laterally towards the dorsal spinal roots under fluoroscopic guidance.
Stimulation Thresholds to a Variety of Stimulus Parameters
Quantify the threshold (minimum charge) stimulus required to evoke sensation and neurophysiological responses during epidural spinal nerve stimulation, and monitor changes in those percepts and responses over time.
Time frame: 30 days
Week 1 Average Stimulus Charge for All Subjects
The average stimulus (nC) required to evoke sensation during week 1 of implant duration.
Time frame: first 7 days of implant
Week 2 Average Stimulus Charge for All Subjects
The average stimulus (nC) required to evoke sensation during week 2 of implant duration.
Time frame: During days 7-14 of implant
Week 3 Average Stimulus Charge for All Subjects
The average stimulus (nC) required to evoke sensation during week 3 of implant duration.
Time frame: During days 15 to 21 of implant
Week 4 Average Stimulus Charge for All Subjects
The average stimulus (nC) required to evoke sensation during week 4 of implant duration.
Time frame: During days 22-28 of implant
Number of Participants Who Were Able to Discern Specific Regions of the Spinal Cord That Evoked Sensations
Evaluate the relationship between stimulation parameters and the modality and naturalness of perceived sensations.
Time frame: 30 days
Qualitative Self-report of Evoked Sensations
Document the subjective perception of cervical 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.
Time frame: 30 days
Change in Pain Ratings After Study Completion
Participants were asked to complete the McGill pain questionnaire at baseline, and weekly throughout implant. We expected to see a decrease in the pain level due to electrical stimulation. A positive score indicates a decrease in level of pain (baseline - study end). Minimum score is 0. Maximum score is 80. The higher the number, the greater the pain. This outcome measure suntracts the baseline pain score from the final pain score. A positive score indicates a reduction in pain from baseline.
Time frame: 30 days
Success Rate During Control of Prosthetic Hand to Identify Object Size
Investigators will test the subject's ability to use a myoelectric prosthetic hand 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 such as pressure at the finger tips or joint angles. In both the presence and absence of stimulation, subjects will be asked to perform tasks such as manipulating blocks, opening a jar, or identifying the stiffness and size of various objects.
Time frame: 30 days
Success Rate During Control of Prosthetic Hand to Identify Object Compliance (Soft, Medium, Hard)
Investigators tested the subject's ability to use a myoelectric prosthetic hand 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 was modulated based on signals recorded from the limb such as pressure at the finger tips or joint angles. In both the presence and absence of stimulation, subjects were asked to perform tasks such as manipulating blocks, opening a jar, or identifying the stiffness (soft, medium, hard) and size of various objects.
Time frame: 30 days
Participants were met in amputee clinics, referred by prosthetics representatives, or responded to advertisements posted at amputee support groups. The study team spoke with approximately 25 interested patients. Of these, four completed the consent process.
| Milestone | Boston Scientific Cord Stimulator Lead |
|---|---|
| Started | 4 |
| Completed | 4 |
| Not completed | 0 |
Quantify the threshold (minimum charge) stimulus required to evoke sensation and neurophysiological responses during epidural spinal nerve stimulation, and monitor changes in those percepts and responses over time.
| milliamps | Boston Scientific Cord Stimulator Lead |
|---|---|
| Stimulation Thresholds to a Variety of Stimulus Parameters | 2.13 (1.25 to 3.75) |
The average stimulus (nC) required to evoke sensation during week 1 of implant duration.
| nC | Boston Scientific Cord Stimulator Lead |
|---|---|
| Week 1 Average Stimulus Charge for All Subjects | 647 (174 to 4000) |
The average stimulus (nC) required to evoke sensation during week 2 of implant duration.
| nC | Boston Scientific Cord Stimulator Lead |
|---|---|
| Week 2 Average Stimulus Charge for All Subjects | 807 (300 to 4384) |
The average stimulus (nC) required to evoke sensation during week 3 of implant duration.
| nC | Boston Scientific Cord Stimulator Lead |
|---|---|
| Week 3 Average Stimulus Charge for All Subjects | 1115 (500 to 4800) |
The average stimulus (nC) required to evoke sensation during week 4 of implant duration.
| nC | Boston Scientific Cord Stimulator Lead |
|---|---|
| Week 4 Average Stimulus Charge for All Subjects | 902 (300 to 3775) |
Evaluate the relationship between stimulation parameters and the modality and naturalness of perceived sensations.
| Participants | Boston Scientific Cord Stimulator Lead |
|---|---|
| Felt stimulation | 4 |
| Felt stim in hand | 4 |
| Felt stim in elbow | 3 |
| Felt stim in shoulder | 2 |
| Felt stim in fingers | 4 |
| C6 evoked stim | 3 |
| C7 evoked stim | 3 |
| C8 evoked stim | 4 |
| T1 evoked stim | 4 |
| T2 evoked stim | 2 |
Document the subjective perception of cervical 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.
| Participants | Boston Scientific Cord Stimulator Lead |
|---|---|
| Paresthetic sensation (primarily) | 1 |
| Mixed Modality (paresthetic and naturalistic) | 2 |
| Naturalistic (primarily) | 1 |
Participants were asked to complete the McGill pain questionnaire at baseline, and weekly throughout implant. We expected to see a decrease in the pain level due to electrical stimulation. A positive score indicates a decrease in level of pain (baseline - study end). Minimum score is 0. Maximum score is 80. The higher the number, the greater the pain. This outcome measure suntracts the baseline pain score from the final pain score. A positive score indicates a reduction in pain from baseline.
| score on a scale | Boston Scientific Cord Stimulator Lead |
|---|---|
| Change in Pain Score (baseline - final) | 14.3 (6 to 20) |
| Baseline Pain Score | 32.3 (29 to 35) |
| Final Pain Score | 18 (12 to 29) |
Investigators will test the subject's ability to use a myoelectric prosthetic hand 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 such as pressure at the finger tips or joint angles. In both the presence and absence of stimulation, subjects will be asked to perform tasks such as manipulating blocks, opening a jar, or identifying the stiffness and size of various objects.
| percentage of success identifying size | Size Discrimination Using Virtual DEKA Arm |
|---|---|
| Success Rate During Control of Prosthetic Hand to Identify Object Size | 74 |
Investigators tested the subject's ability to use a myoelectric prosthetic hand 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 was modulated based on signals recorded from the limb such as pressure at the finger tips or joint angles. In both the presence and absence of stimulation, subjects were asked to perform tasks such as manipulating blocks, opening a jar, or identifying the stiffness (soft, medium, hard) and size of various objects.
| percentage of success identifying compli | Compliance Discrimination Using DEKA Arm |
|---|---|
| Success Rate During Control of Prosthetic Hand to Identify Object Compliance (Soft, Medium, Hard) | 60 |
Collected over 30 days (duration of implant). Non-serious events are listed at a 1% frequency threshold.
| Group | Deaths | Serious | Other |
|---|---|---|---|
| Boston Scientific Cord Stimulator Lead | 0/4 (0%) | 0/4 (0%) | 2/4 (50%) |
| Event | Boston Scientific Cord Stimulator Lead |
|---|---|
| Lead migrationSurgical and medical procedures | 2/4 |
The first participant experienced lead migration and early explant. This participant was later re-enrolled and completed study activities. Therefore, there are 4 unique individuals counted among the 5 consented participants.
| Age, Categorical(Participants) | Boston Scientific Cord Stimulator Lead |
|---|---|
| <=18 years | 0 |
| Between 18 and 65 years | 3 |
| >=65 years | 1 |
| Sex: Female, Male(Participants) | Boston Scientific Cord Stimulator Lead |
|---|---|
| Female | 3 |
| Male | 1 |
| Ethnicity (NIH/OMB)(Participants) | Boston Scientific Cord Stimulator Lead |
|---|---|
| Hispanic or Latino | 0 |
| Not Hispanic or Latino | 4 |
| Unknown or Not Reported | 0 |
| Race (NIH/OMB)(Participants) | Boston Scientific Cord Stimulator Lead |
|---|---|
| American Indian or Alaska Native | 0 |
| Asian | 0 |
| Native Hawaiian or Other Pacific Islander | 0 |
| Black or African American | 1 |
| White | 3 |
| More than one race | 0 |
| Unknown or Not Reported | 0 |
| Region of Enrollment(participants) | Boston Scientific Cord Stimulator Lead |
|---|---|
| United States | 4 |
| Participants with phantom limb pain(Participants) | Boston Scientific Cord Stimulator Lead |
|---|---|
| Count of participants | 3 |
Documents are hosted by the registry — open the source record to download them.
Plan to share: Yes — Study sponsors will have access to research data and documents in order to monitor the integrity of the study.
Supporting information: Study protocol, Sap, Icf
This study is completed, as verified in Sep 2025. You cannot join it, but the record below documents what was studied.
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Lee Fisher, PhD