DRG Stimulation for Complex Regional Pain Syndrome

Overseen By Daniel Torrez, BS

Age: 18+

Sex: Any

Trial Phase: Academic

Sponsor: Rush University Medical Center

Must not be taking: Corticosteroids

Disqualifiers: Lead migration, Other neuromodulation, others

No Placebo Group All trial participants will receive the active study treatment (no placebo)

Compensation: Varies

Number of Visits: 9

30 Participants Needed

Trial Summary

Will I have to stop taking my current medications?

The trial does not specify if you need to stop taking your current medications, but it does mention that you should not have changing or unstable pain medications within 30 days before joining. It's best to discuss your specific medications with the trial team.

What data supports the effectiveness of the treatment DRG stimulation for Complex Regional Pain Syndrome?

Research shows that dorsal root ganglion (DRG) stimulation is effective for treating complex regional pain syndrome (CRPS) and other chronic pain conditions, providing sustained pain relief. It is considered more effective than spinal cord stimulation for CRPS and has been used successfully for various chronic pain syndromes. ^{1 2 3 4 5}

Is DRG stimulation generally safe for humans?

Dorsal root ganglion (DRG) stimulation has been used safely in thousands of patients since its first approval in 2011, with studies indicating it provides effective pain relief with complications similar to other neuromodulation techniques. ^{2 4 5 6 7}

How is DRG stimulation treatment different from other treatments for complex regional pain syndrome?

DRG stimulation is unique because it specifically targets the dorsal root ganglion, which can provide more focused pain relief compared to traditional spinal cord stimulation. It has shown superior efficacy for complex regional pain syndrome and is a newer form of neuromodulation with promising results for chronic pain management. ^{1 2 4 5 7}

What is the purpose of this trial?

This study seeks to evaluate the use of intermittent dosing as an alternative paradigm for patients with DRG stimulation in place for at least 1 year and minimum 50% pain relief in the targeted area. Patients will be prospectively randomized to one of two stimulation paradigms both of which involve intermittent dosing at 30 seconds ON and 90 seconds OFF. Group 1 will have their frequency set at 20 Hz with amplitude levels adjusted in order to remain in the therapeutic window (subthreshold stimulation). Group 2 will have their frequency set at 5 Hz with amplitude levels adjusted in order to remain in the therapeutic window (subthreshold stimulation) This study will be performed in a crossover fashion, meaning patients will be changed to the alternate dosing regimen at the 13-week time period. Patients will be seen and evaluated prior to randomization and reprogramming, and thereafter evaluated at 4, 8, and 12-weeks. At the 12-week time period, patients will begin a 1-week washout period of continuous stimulation. At the 13-week time period, patients will be evaluated, crossed over to the other study arm and thereafter evaluated at 17, 21, and 25-weeks.

Research Team

Robert McCarthy, PharmD

Principal Investigator

Rush University Medical Center

Eligibility Criteria

This trial is for adults aged 18-99 with chronic back or leg pain who've had significant pain relief from a DRG stimulator for at least a year. They should have followed up recently, been reprogrammed before, and be willing to follow the study plan and complete health surveys.

Inclusion Criteria

I have used the Abbott PROCLAIM XR system for over a year for my chronic back or leg pain.

I've had over 50% pain relief in a specific area in the past year.

Must have been seen for routine follow-up within last 4 months

Exclusion Criteria

Other concurrent neuromodulation system in place

Significant lead migration as determined by clinician

I have missed doses or my treatment failed in the last 6 months.

Timeline

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

1 visit (in-person)

Randomization and Initial Evaluation

Participants are randomized into one of two stimulation paradigms and evaluated prior to reprogramming

1 week

1 visit (in-person)

Treatment Phase 1

Participants receive DRG stimulation therapy with intermittent dosing, evaluated at 4, 8, and 12 weeks

12 weeks

3 visits (in-person)

Washout and Crossover

Participants undergo a 1-week washout period followed by crossover to the alternate study arm

1 week

1 visit (in-person)

Treatment Phase 2

Participants receive the alternate DRG stimulation therapy, evaluated at 17, 21, and 25 weeks

12 weeks

3 visits (in-person)

Follow-up

Participants are monitored for safety and effectiveness after treatment

4 weeks

Treatment Details

Interventions

• DRG stimulation 20 Hz 30/90
• DRG stimulation 5 Hz 30/90

Trial Overview The study tests two intermittent dosing patterns of DRG stimulation as alternatives to continuous therapy. Participants will try both methods: one with higher frequency (20 Hz) and another with lower (5 Hz), switching after 13 weeks, to see which works better for pain management.

Participant Groups

Group I: DRG stimulation therapy at 20 Hz and 30 seconds ON, 90 seconds OFF Active Control 1 Intervention

DRG stimulation therapy at 20 Hz (30 seconds ON, 90 seconds OFF)

Group II: DRG stimulation therapy at 5 Hz and 30 seconds ON, 90 seconds OFF Active Control 1 Intervention

DRG stimulation therapy at 5 Hz (30 seconds ON, 90 seconds OFF)

DRG stimulation 20 Hz 30/90 is already approved in European Union, United States for the following indications:

Approved in European Union as Dorsal Root Ganglion Stimulation for:

• Chronic pain
• Neuropathic pain
• Complex Regional Pain Syndrome (CRPS)
• Radiculopathy

Approved in United States as Dorsal Root Ganglion Stimulation for:

• Chronic pain
• Neuropathic pain
• Complex Regional Pain Syndrome (CRPS)
• Radiculopathy

Who Is Running the Clinical Trial?

Rush University Medical Center

Lead Sponsor

Trials

448

Recruited

247,000+

Findings from Research

Dorsal root ganglion (DRG) stimulation has shown effectiveness in treating chronic neuropathic postsurgical pain (NPP) specifically in areas like the groin, knee, and foot, based on a review of existing literature.

Conditions such as pain following thoracotomy, hernia surgery, and knee replacement surgery are identified as likely benefiting from DRG stimulation, although more prospective studies are needed to validate these findings against the growing clinical experience.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Neuromodulation of the Dorsal Root Ganglion for Chronic Postsurgical Pain. Antony, AB., Schultheis, BC., Jolly, SM., et al.[2020]

In a study of 20 patients with complex regional pain syndrome (CRPS) of the upper extremities, 85% achieved at least 50% pain relief after dorsal root ganglion (DRG) neuromodulation, with sustained relief reported at six months.

While DRG neuromodulation significantly reduced pain and opioid use, it was associated with a 30% complication rate, including one serious case of reversible spinal cord compression.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Efficacy and Safety of Cervical and High-Thoracic Dorsal Root Ganglion Stimulation Therapy for Complex Regional Pain Syndrome of the Upper Extremities. Graca, MJ., Lubenow, TR., Landphair, WR., et al.[2023]

A systematic review of 28 studies involving 354 patients indicates that dorsal root ganglion stimulation (DRGS) can lead to over 50% pain reduction in various non-CRPS chronic pain syndromes, such as axial low back pain and chronic pelvic pain.

Patients receiving DRGS also reported significant improvements in physical function, quality of life, and reduced reliance on pain medications, although the evidence is primarily from lower-level studies, highlighting the need for more rigorous research.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Dorsal Root Ganglion Stimulation for the Treatment of Non-Complex Regional Pain Syndrome Related Chronic Pain Syndromes: A Systematic Review. Stelter, B., Karri, J., Marathe, A., et al.[2022]

Dorsal root ganglion stimulation (DRGS) shows a low infection risk during the trial stage (1.03%), but the risk significantly increases during the implant stage (4.80%), indicating a need for careful monitoring and prophylaxis during this procedure.

This systematic review analyzed data from 10 studies involving 567 patients, providing the first comprehensive look at infection rates associated with DRGS at different stages, highlighting the importance of further research into infection management in this treatment.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Infectious Complications of Dorsal Root Ganglion Stimulation: A Systematic Review and Pooled Analysis of Incidence. Moman, RN., Peterson, AA., Maher, DP., et al.[2022]

In a study of 93 patients receiving dorsal root ganglion (DRG) stimulation for pain relief, those with a history of chronic opioid use were less likely to achieve significant pain relief (≥50% or ≥80%) at multiple follow-up points (1 month, 3 months, and 12 months).

The findings suggest that prior chronic opioid use may negatively impact the effectiveness of DRG stimulation, indicating that patient history should be considered when predicting treatment outcomes.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Effect of Patient Characteristics on Clinical Outcomes More Than 12 Months Following Dorsal Root Ganglion Stimulation Implantation: A Retrospective Review. Hagedorn, JM., McArdle, I., D'Souza, RS., et al.[2022]

In a study of 66 participants with chronic pain, dorsal root ganglion (DRG) stimulation led to a significant reduction in pain levels, with average pain ratings dropping from 8.0 cm to 4.1 cm after 12 months, and 49% of subjects experiencing at least a 50% reduction in pain.

The treatment also improved functional capacity, mood, and quality of life, with a high success rate of permanent implants (86.2%) and a low incidence of complications such as infections or lead migrations.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Evaluating Dorsal Root Ganglion Stimulation in a Prospective Dutch Cohort. Huygen, FJPM., Liem, L., Nijhuis, H., et al.[2022]

Dorsal root ganglion stimulation (DRGS) has shown promising results in treating neuropathic pain, particularly in conditions like complex regional pain syndrome (CRPS) and causalgia, with Class A randomized clinical trial evidence indicating it provides superior pain relief compared to spinal cord stimulation (SCS).

While DRGS has been effective for various pain types, including postsurgical pain and phantom pain, its success in treating failed back surgery syndrome (FBSS) is less clear, and long-term outcomes are still needed to fully understand its efficacy across different pain conditions.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

The Efficacy and Safety of Dorsal Root Ganglion Stimulation as a Treatment for Neuropathic Pain: A Literature Review. Harrison, C., Epton, S., Bojanic, S., et al.[2022]

References

1. England pubmed.ncbi.nlm.nih.gov

Neuromodulation of the Dorsal Root Ganglion for Chronic Postsurgical Pain. [2020]

2. United States pubmed.ncbi.nlm.nih.gov

Efficacy and Safety of Cervical and High-Thoracic Dorsal Root Ganglion Stimulation Therapy for Complex Regional Pain Syndrome of the Upper Extremities. [2023]

3. United States pubmed.ncbi.nlm.nih.gov

Dorsal Root Ganglion Stimulation for the Treatment of Non-Complex Regional Pain Syndrome Related Chronic Pain Syndromes: A Systematic Review. [2022]

4. United States pubmed.ncbi.nlm.nih.gov

Infectious Complications of Dorsal Root Ganglion Stimulation: A Systematic Review and Pooled Analysis of Incidence. [2022]

5. United States pubmed.ncbi.nlm.nih.gov

Effect of Patient Characteristics on Clinical Outcomes More Than 12 Months Following Dorsal Root Ganglion Stimulation Implantation: A Retrospective Review. [2022]

6. United States pubmed.ncbi.nlm.nih.gov

Evaluating Dorsal Root Ganglion Stimulation in a Prospective Dutch Cohort. [2022]

7. United States pubmed.ncbi.nlm.nih.gov

The Efficacy and Safety of Dorsal Root Ganglion Stimulation as a Treatment for Neuropathic Pain: A Literature Review. [2022]