Closed Loop Spinal Cord Stimulation for Complex Regional Pain Syndrome

Efficacy of Closed-Loop Spinal Cord Stimulation for Complex Regional Pain Syndrome

The primary purpose of this study is to determine the differences in response to treatment of complex regional pain syndrome with a closed-loop spinal cord stimulator if applied in the early phases (acute or subacute) versus the chronic phase.

Study Overview

• Status: Recruiting
• Conditions: Complex Regional Pain Syndromes
• Intervention / Treatment: Device: Spinal Cord Stimulation Device

Detailed Description

After being informed about the study and the potential risks, all patients given written informed consent will be organized into group 1 (acute or subacute) and group 2 (chronic). They will undergo a trial period with a temporary spinal cord stimulator for 7 days. After the trial period, if the provider determines the device improved the patient's pain and function, the permanent device will be implanted. The patient will fill out an outcomes packet at baseline, end of trial period, 3 months and 6 months. There will also be a blood draw to evaluate prolactin levels, which are associated with stress and pain, at baseline, end of trial period, and 3 months.

• Study Type: Interventional
• Enrollment (Estimated): 32
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Julie C McCauley; Phone Number: 585-554-7122; Email: mccauley.julie@scrippshealth.org
• Study Contact Backup: Name: Roslyn M Kackman; Phone Number: 858-554-7122; Email: kackman.roslyn@scrippshealth.org

Study Locations

• United States
  • California
    • La Jolla, California, United States, 92037
      • Recruiting
      • Scripps Clinic Torrey Pines
      • Contact: Julie C McCauley; Phone Number: 585-554-7122; Email: mccauley.julie@scrippshealth.org
      • Contact: Roslyn M Kackman; Phone Number: 858-554-7122; Email: kackman.roslyn@scrippshealth.org
      • Principal Investigator: David B Hiller, MD

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• 18 years or older
• neuromodulation naive patients with unilateral CRPS type 1 or type 2 (defined by Budapest Criteria)
• pre-procedure psychological clearance

Exclusion Criteria:

• younger than 18 years
• prior neuromodulation including spinal cord stimulation
• prior dorsal root ganglion stimulation
• prior peripheral nervous system stimulation
• anatomical obstacles to dorsal column lead placement

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Non-Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Acute and Subacute Phases of CRPS; Participants diagnosed with acute and subacute phases of CRPS will be assigned to this group.	Device: Spinal Cord Stimulation Device; The closed-loop spinal cord stimulation mechanism uses dynamic adjusting stimulation parameters based on real-time physiologic response and is uniquely positioned to mitigate the aberrant inflammatory and neurosensory processing and autonomic dysfunction driving CRPS and its progression between phases.
Experimental: Chronic Phase of CRPS; Participants diagnosed with chronic CRPS will be assigned to this group.	Device: Spinal Cord Stimulation Device; The closed-loop spinal cord stimulation mechanism uses dynamic adjusting stimulation parameters based on real-time physiologic response and is uniquely positioned to mitigate the aberrant inflammatory and neurosensory processing and autonomic dysfunction driving CRPS and its progression between phases.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in Complex Regional Pain Syndrome Severity Scores	(CRPS SS) This will be determined at baseline by the provider based on his diagnosis of the patient's condition, being acute and subacute or chronic. This is based on the presence or absence of 16 clinically-assessed signs and symptoms, and complements the diagnostic criteria for CRPS. A higher score indicates greater severity of the condition. This will be followed up at the 7 day trial period, 3 months and 6 months post procedure by evaluation.	Baseline, 7 day trial period, 3 months, 6 months
Change in Target Activation Amplitude Levels by the Spinal Cord Stimulation Device	Spinal cord stimulation device parameters will be collected to determine if a lower voltage is required to treat acute phase of complex regional pain syndrome as compared to later phases. This will be conducted at follow up visits and analyzed by the medical device representative. The data will be pulled and analyzed to determine the activation point for each patient. This will be captured at the 7 day trial period, 3 months, and 6 months.	7 day trial period, 3 months, and 6 months.

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in Prolactin Levels	We plan to include a physiological marker of pain response by assessing serum prolactin levels, which are linked to dopamine levels in the brain. We will use prolactin as a convenient marker of abnormal dopamine levels due to chronic pain and the response to spinal cord stimulation treatment as an objective quantifiable metric of success with treatment. We will collect this via blood draw at our lab at baseline, at the 7 day trial period, and 3 months.	Baseline, 7 day trial period, and 3 months
Visual Analogue Pain Scale	(VAS) This will be used to determine the pain intensity the patient is experiencing. It will be on a scale from 0-10, 0 being no pain and 10 being the worst pain.	Baseline, 7 day trial period, 3 months, and 6 months
Quality of Life Questionnaire	(EQ-5D-5L) Used to capture quality of life across 5 domains: mobility, self-care, usual activities, pain/discomfort, and anxiety/depression. A lower score would indicate a severe score and the patient has a low quality of life. The patient also rates how good or bad their health is on a scale of 0-100, 100 being the best health and 0 being the worst health they could imagine.	Baseline, 7 day trial period, 3 months, and 6 months
Patient Reported Outcomes Measurement Information System-29 v 2.1	(PROMIS-29v2.1) Used to assess pain intensity using a single 0-10 numeric rating item and seven health domains: physical function, fatigue, pain interference, depressive symptoms, anxiety, ability to participate in social roles and activities, and sleep disturbance.	Baseline, 7 day trial period, 3 months, and 6 months
General Anxiety Disorder-7	(GAD-7) Used for the screening and severity measuring of generalized anxiety disorder. It consists of seven items the patients rate based on their experiences over the past two weeks. Each item is scored from 0 (none) to 3 (every day). The cumulative score, ranging from 0-21, indicates the severity of GAD symptoms, with higher scores corresponding to greater anxiety levels.	Baseline, 7 day trial period, 3 months and 6 months.
Patient Health Questionnaire-9	(PHQ-9) Used for screening and measuring the severity of depression. A higher score would indicate the patient has a worse outcome.	Baseline, 7 day trial period, 3 months, 6 months
Short-Form McGill Pain Questionnaire-2	(SF-MPQ-2) Used to rate the intensity of each type of pain and related symptoms. A higher score means the patient has a worse outcome. They rate their pain and symptoms on a scale of 0-10, with a 0 being no pain and 10 being the worst pain.	Baseline, 7 day trial period, 3 months, 6 months
Pain Catastrophizing Scale	(PCS) Used to assess catastrophic thinking related to pain among adults with or without chronic pain. A higher score would mean the patient has a worse outcome.	Baseline, 7 day trial period, 3 months, 6 months
Patient Global Impression of Change	(PGIC) Used to measure the patient's belief about the effectiveness of the treatment. A higher score would reflect the patient believes the treatment is not effective and they have been doing much worse.	7 day trial period, 3 months and 6 months
Amount of Pain Medication Consumed by Patient	Used to track amount of pain medication taken by the patient on a daily basis or what they are taking and when they are taking it.	Baseline, 7 day trial period, 3 months and 6 months

Collaborators and Investigators

• Sponsor: Scripps Health
• Investigators: Principal Investigator: David B Hiller, MD, Physician

Study record dates

Study Major Dates

• Study Start (Actual): September 3, 2024
• Primary Completion (Estimated): June 1, 2026
• Study Completion (Estimated): June 1, 2026

Study Registration Dates

• First Submitted: May 8, 2024
• First Submitted That Met QC Criteria: May 15, 2024
• First Posted (Actual): May 20, 2024

Study Record Updates

• Last Update Posted (Estimated): November 3, 2025
• Last Update Submitted That Met QC Criteria: October 30, 2025
• Last Verified: October 1, 2025

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Nervous System Diseases; Neuromuscular Diseases; Peripheral Nervous System Diseases; Autonomic Nervous System Diseases; Complex Regional Pain Syndromes
• Other Study ID Numbers: 24-8347

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: Yes
• product manufactured in and exported from the U.S.: No