ClinicalTrials.gg
WithdrawnNCT04725006Updated Oct 15, 2025

Sensory Responses to Dorsal Root Stimulation

An observational study in Amputation and Sensation, Phantom, sponsored by Lee Fisher, PhD. Withdrawn at 1 site in United States. Open to participants aged 18 Years to 70 Years. Per ClinicalTrials.gov, last updated 2025-10-15.

Sponsored by Lee Fisher, PhD · Observational

Why this study was withdrawn
No participant/patient opportunities for testing. Received funding for a different study.
Study type
Observational
Model
Case-only
Time perspective
Prospective
Enrollment
0
Ages
18 Years to 70 Years
Sex
All
01

Study summary

The goal of this project is to characterize the types of sensations that can be evoked via electrical stimulation of the spinal cord and spinal nerves. Patients will be recruited from a local pain clinic, each with a spinal cord stimulation device implanted, to participate in experiments to explore the ability to modulate and control the modality, intensity, focality, and location of the sensations evoked by stimulation through the spinal cord stimulator leads. Investigators will connect spinal cord stimulator leads to a custom stimulator system and will ask subjects to report the types of sensations felt. Invesigators will also perform detailed psychophysical metrics to examine participants' ability to discriminate sensations.

Read the detailed description

For this study, investigators aim to determine whether DRG and spinal root stimulation might be viable techniques for restoring feedback. Investigators will focus on patients undergoing temporary percutaneous trials of DRG or lateral spinal cord stimulation with leads manufactured by either Boston Scientific (under PMA P030017) or St. Jude (under PMA P150004), which have FDA premarket approval for the management of chronic pain in the trunk and lower limbs. In this early experiment, investigators will not focus on individuals with limb loss, but rather will include patients already undergoing a percutaneous trial of DRG or spinal root stimulation to treat pain. Investigators will characterize the location, modality, and intensity of sensations evoked in the hands or feet with stimulation delivered by an external stimulator.

02

Conditions studied

  • Amputation
  • Sensation, Phantom

Keywords

  • spinal cord stimulation
  • dorsal root ganglia stimulation
  • sensation
  • amputation
  • pain
03

In context

Phantom Limb

163 studies on the registry are indexed under Phantom Limb; 35 are open to participants now.

Browse Phantom Limb studies →

Lead sponsor

Lee Fisher, PhD is the lead sponsor of 4 studies on the registry; none are open to participants now.

Counted across the registry records on this site, refreshed daily.

04

Who can participate

Ages eligible
18 Years to 70 Years
Sexes eligible
All
Accepts healthy volunteers
No
Sampling method
Probability sample

Study population

Individuals undergoing a 7-day trial period of percutaneous DRG or spinal root stimulation.

Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.

Inclusion criteria

  1. Subjects must be between the ages of 18 and 70 years old.
  2. Subjects must be undergoing an epidural spinal cord implanted electrode array clinical trial with Dr. Helm for the management of pain.
  3. Persons must understand the consent and the procedures.

Exclusion criteria

Exclusion Criteria:

  1. Persons with open wounds;
  2. Persons with implanted metal rods in the spine or limbs;
  3. Persons with defibrillator or pacemaker;
  4. Persons with permanent skin metal tags or decorations.
05

Study design

Observational model
Case-only
Time perspective
Prospective
Enrollment
0 participants (actual)
Patient registry
No

Groups and cohorts

  • Stimulation in individuals with implanted stimulation systems

    During psychophysical stimulation trials, an external stimulator will be connected to the SCS lead, a volley of stimulation will be performed, and the subject will be asked to respond to standard psychophysical questions, as well as to provide any additional comments.

    Device: Spinal cord stimulation system

Interventions

  • DeviceSpinal cord stimulation system

    These systems are indicated as an aid in the management of chronic intractable pain of the trunk and/or limbs, including unilateral or bilateral pain associated with the following: failed back surgery syndrome, intractable low back pain and leg pain. Stimulation will be applied to the system using an external stimulator to see if sensations can be evoked in the participant's limb/foot.

    Also known as: Boston Scientific, St. Jude

06

What researchers measure

Primary outcomes

  1. Location of evoked sensory percepts

    Document where on the body the subject perceives the stimulation locations.

    Time frame: up to 2 days

  2. Stimulation perceptual thresholds to stimulus parameters

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

    Time frame: up to 2 days

  3. Stimulation neurophysiology thresholds to stimulus parameters

    Quantify the threshold stimulus required to evoke neurophysiological responses during epidural spinal nerve stimulation

    Time frame: up to 2 days

Secondary outcomes

  1. Qualitative self-report of evoked sensations

    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.

    Time frame: up to 2 days

07

Study locations

1 site
  • University of Pittsburgh
    Pittsburgh, Pennsylvania 15213, United States
08

References and documents

Individual participant data

Plan to share: No

No publications or documents are linked to this record.

09

Timeline

Tracking since Sep 25, 2026
ElapsedEstimatedEstimated, not yet reached

Ran from Dec 2020 to primary completion in Jul 2025, 54 months.

How these figures are worked out, and which studies are left out of them.

Registered
Jan 21, 2021
First posted
Jan 26, 2021
StartActual
Dec 16, 2020
Primary completionActual
Jul 11, 2025
CompletionActual
Oct 7, 2025
Last update
Oct 15, 2025
What these dates mean
Start.
When the first participant enrolled; while estimated, when the study expects to open to recruitment.
Primary completion.
When the last participant was examined or treated to collect data for the study's main question, its primary outcome. A study that stopped early gives the date its data collection stopped.
Completion.
When the last participant's last visit took place, for every outcome, secondary ones and side effects included: the end of the study. Often later than primary completion, sometimes the same day.
Actual and Est.
Actual means the registry says the date has happened. Est. (estimated) is a date the sponsor plans or expects. It can still move, and the sponsor is expected to change it to actual once it has passed.
No changes since tracking began. The registry record was last updated on Oct 15, 2025, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗
10

Registry details

Key details

Study ID
NCT04725006
Lead sponsor
Lee Fisher, PhD
Responsible party
Lee Fisher, PhD (Assistant Professor, University of Pittsburgh) — Sponsor-investigator
First posted
Jan 26, 2021
Start date
Dec 16, 2020
Primary completion
Jul 11, 2025
Completion
Oct 7, 2025
Last update
Oct 15, 2025

Study contacts

Lee Fisher, PhD
principal investigator · University of Pittsburgh

Oversight

Data monitoring committee
No
FDA-regulated drug
No
FDA-regulated device
Yes
View the source record on ClinicalTrials.gov ↗

Not currently enrolling

This study is withdrawn, as verified in Oct 2025. You cannot join it, but the record below documents what was studied.

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