Effect of Spinal Cord Stimulation on Pain Thresholds and Sensory Perception in Chronic Pain Patients. (SCS)

The purpose of this study is to better understand how the Spinal Cord Stimulator works in relieving chronic pain.

The investigators are asking subject to take part in this study because who are chronic pain patients who already have a Spinal Cord Stimulator (SCS) in place.

The investigators hypothesize that chronic pain patients will have higher heat pain threshold and heat pain tolerance over the painful areas with the SCS on.

QST (Quantitative Sensory Testing, a heat/cold simulation test) might be an objective helpful tool for prudent patient selection for an expensive and invasive procedure for future SCS placement.

Study Overview

• Status: Completed
• Conditions: Chronic Pain

Detailed Description

Sixty subjects who already have an implanted SCS device for pain management at the MGH Center for Pain Medicine and other Partners affiliated pain centers will be enrolled.

Inclusion Criteria:

1. Subject is 18 years or older.
2. Subject has an SCS device implanted for at least one month for pain control. This requirement is set to ensure that the subject becomes familiarized with the therapy and has recovered from the surgical implantation of the SCS device.

Exclusion Criteria:

1. Subject has neurological disease or a condition causing sensory deficit to the painful area.
2. Subject had recent therapy that may influence QST results, e.g., neuroablative procedure within two-months.
3. Subjects who are unable to travel to the study center.

It will be a one time outpatient visit study, which will include the following:

1. Brief pain history and Neurological examination

   • Medical History (including medication use);
   • Pain location, intensity, character and if known, etiology, duration;
   • Maps of pain locations and paresthesia locations;
   • Sensory neurological examination (e.g., alcohol swab, cotton swab, pinprick and vibration);
   • A check on routine vital signs (blood pressure, pulse, pulse oximetry).

2. QST will include the following:

   • Warm sensation, heat pain threshold, heat pain tolerance and wind-up. A cut-off of 53°C for heat will be preset to avoid tissue damage.
   • QST will be done on two areas; painful area and non-painful area without paresthesia with the SCS turned off.
   • Subject will then turn on SCS and a repeat QST will be performed on the painful and non-painful areas.
   • QST tests will be performed in a quiet room at temperature 25º 2° C. The time and duration of the QST tests will be recorded.

QST will be performed at least 4 hours and no later than 6 hours after the last dose of long acting opioid and after last SCS on time. In this way the investigators will try to avoid recording possible end dose withdrawal and provide sufficient time for the subject to return to baseline for their SCS therapy.

• Study Type: Observational
• Enrollment (Actual): 19

Contacts and Locations

Study Locations

• United States
  • Massachusetts
    • Boston, Massachusetts, United States, 02114
      • MGH Center for Translational Pain Research

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

• Sampling Method: Non-Probability Sample

Study Population

Sixty subjects who already have an implanted SCS device for pain management at the MGH Center for Pain Medicine and other Partners affiliated pain centers will be enrolled.

Description

Inclusion Criteria:

• Subject is 18 years or older.
• Subject has an SCS device implanted for at least one month for pain control. This requirement is set to ensure that the subject becomes familiarized with the therapy and has recovered from the surgical implantation of the SCS device.

Exclusion Criteria:

• Subject has neurological disease or a condition causing sensory deficit to the painful area.
• Subject had recent therapy that may influence QST results, e.g., neuroablative procedure within two-months.
• Subjects who are unable to travel to the study center.

Study Plan

How is the study designed?

Design Details

• Observational Models: Case-Only
• Time Perspectives: Cross-Sectional

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Warm Sensation (WS) Threshold- Pain Site	WS threshold is a type of Quantitative Sensory Test (QST). A contact thermode was attached to the subject's painful area that has SCS coverage. The thermode increased by 1°C/sec from a baseline of 32°C. Subjects were instructed to stop stimulation when they first perceived a warm sensation. Subjects performed this test with their SCS off and again with their SCS on.	WS threshold is assessed once at Visit 1
Heat Pain (HP) Threshold- Pain Site	Heat Pain threshold is a type of QST. A contact thermode was attached to the subject's painful area that has SCS coverage. The thermode increased by 1°C/sec from a baseline of 32°C. Subjects were instructed to stop the stimulation when pain was first detected. Subjects performed this test with their SCS off and again with their SCS on.	HP threshold is assessed once at Visit 1
Heat Pain Tolerance- Pain Site	Heat Pain threshold is a type of QST. A contact thermode was attached to the subject's painful area that has SCS coverage. The thermode increased by 1°C/sec from a baseline of 32°C. Subjects were instructed to stop the stimulation when pain was no longer tolerable. Subjects performed this test with their SCS off and again with their SCS on.	Heat Pain Tolerance is assessed once at Visit 1

Collaborators and Investigators

• Sponsor: Massachusetts General Hospital
• Investigators: Principal Investigator: Shihab Ahmed, MD, Massachusetts General Hospital

Study record dates

Study Major Dates

• Study Start: June 1, 2010
• Primary Completion (Actual): August 1, 2011
• Study Completion (Actual): December 20, 2016

Study Registration Dates

• First Submitted: June 3, 2010
• First Submitted That Met QC Criteria: June 3, 2010
• First Posted (Estimate): June 4, 2010

Study Record Updates

• Last Update Posted (Actual): July 22, 2020
• Last Update Submitted That Met QC Criteria: July 21, 2020
• Last Verified: July 1, 2020

More Information

Terms related to this study

• Keywords: spinal cord stimualtor
• Additional Relevant MeSH Terms: Pain; Neurologic Manifestations; Chronic Pain
• Other Study ID Numbers: 2010P 000425

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: No