Autonomic Dysfunction and Spinal Cord Stimulation in Complex Regional Pain Syndrome (CRPS)

Autonomic Dysfunction and Spinal Cord Stimulator in Complex Regional Pain Syndrome

To demonstrate that spinal cord stimulator has an effect on sympathetic function (the one that give us the fight and flight response). Therefore, if the spinal cord stimulator has an effect on sympathetic function, the responses from CRPS patients to different stimuli will differ significantly pre and post SCS implant.

If CRPS patients exhibit autonomic, CRPS patients could be stratified according to their sympathetic function pre-implant. It is expected that patients with a moderate/mild form of autonomic dysfunction will have better outcomes with the SCS.

Study Overview

• Status: Terminated
• Conditions: Complex Regional Pain Syndrome
• Intervention / Treatment: Other: Autonomic Function Assessment

Detailed Description

Currently the mechanisms of Complex Regional Pain Syndrome (CRPS) are poorly understood and stratification of either diagnosis or therapy is very weak. . There is a great need to develop and validate more objective methods to characterize and stratify CRPS that better diagnostic and therapeutic approaches are available. Spinal Cord Stimulation (SCS) has been used as the last resource to alleviate pain and re-establish function in CRPS patients. However, there is a disagreement over how it works. An underlying concept is that it works by modulating autonomic nervous system (ANS) activity. Therefore, ANS parameters could be useful to stratify patients. Our preliminary studies indicated that SCS has also an effect on blood pressure regulation and improves the CRPS patients' response to Valsalva maneuver -a test of autonomic function. The Autonomic Nervous System function in adult CRPS patients has not yet been studied. The only existing study of CRPS and autonomic function showed that 15% of the patients suffer from syncope and increased heart rate during upright position similar to same aged patients with postural tachycardia syndrome - a syndrome of autonomic dysfunction. It is unclear if autonomic dysfunction is present in CRPS patients because ANS activity is altered by chronic pain or whether or not ANS activity contributes to CRPS. Therefore, we proposed to study the autonomic function in CRPS patients by standardized autonomic function and to evaluate the effect of the SCS on autonomic function in CRPS patients before and after spinal cord stimulator implant. This is a 24 months study.

• Study Type: Interventional
• Enrollment (Actual): 10
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United States
  • Tennessee
    • Nashville, Tennessee, United States, 37212
      • Vanderbilt University

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 65 years (Adult, Older Adult)
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• CRPS patients meeting the inclusion criteria according to the International Association for the Study of pain task Force will be included in the study.
• Age: 18 to 65.
• Disease duration of at least 6 months.
• History of unsuccessful long lasting therapies: physical therapy, transcutaneous electrical stimulation and medication.

Exclusion Criteria:

• Presence of current or past pulmonary, hepatic, renal disease, arthritis, hematopoietic, and neurological diseases not related to CRPS.
• Anticoagulant therapy, cardiac pacemaker used.
• Pregnancy test for females is positive.

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
Placebo Comparator: CRPS patients without spinal cord stimulation; CRPS patients declining spinal cord stimulation therapy. Autonomic Function will be assessed at baseline and again within 2 years.	Other: Autonomic Function Assessment
Experimental: CRPS patients: candidates for spinal cord stimulator; CRPS patients who are candidates for spinal cord stimulator implant. These patients will have Autonomic Function assessments before and after the Standard of Care spinal cord stimulation implant	Other: Autonomic Function Assessment

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in muscle sympathetic nerve activity	Electrical neurography data from sympathetic nerves	At baseline and within 2 years

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Heart rate	Heart rate (bpm)	At baseline and within 2 years
Blood pressure response	Blood pressure (mmHg)	At baseline and within 2 years

Collaborators and Investigators

• Sponsor: Vanderbilt University Medical Center
• Investigators: Principal Investigator: Peter Konrad, M.D., Vanderbilt University

Study record dates

Study Major Dates

• Study Start: January 1, 2008
• Primary Completion (Actual): January 1, 2010
• Study Completion (Actual): January 1, 2010

Study Registration Dates

• First Submitted: May 8, 2008
• First Submitted That Met QC Criteria: October 24, 2008
• First Posted (Estimated): October 27, 2008

Study Record Updates

• Last Update Posted (Actual): July 27, 2026
• Last Update Submitted That Met QC Criteria: July 23, 2026
• Last Verified: July 1, 2026

More Information

Terms related to this study

• Keywords: CRPS; SCS; RSD
• 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: 071060; CTSA 1 UL 1 RR024975 NCRR/NIH

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No