Capsaicin-induced Muscle Pain in Humans

NCT02377180 | Completed

• 1 other identifier: 066/13
• Study Type: interventional
• Target: 72
• Locations: 1 country
• Sites: 1

Brief Summary

There is currently no specific diagnostic test for primary muscular pain. The present study investigates whether selective blockade of the suprascapular nerve can effectively abolish experimental pain arising from the supraspinatus muscle. Experimental muscle pain is induced by intramuscular injection of capsaicin, an alkaloid from red chili peppers. The study consists of three parts:

1. 1.to describe the development, time course and intensity of capsaicin-induced muscle pain
2. 2.to evaluate the effectiveness of suprascapular nerve block against capsaicin-induced muscle pain
3. 3.to compare suprascapular nerve block and direct intramuscular local anesthetic infiltration for their effectiveness in capsaicin-induced muscle pain

Conditions

Healthy

Keywords

musculoskeletal pain; regional anesthesia; diagnostic nerve block; intramuscular capsaicin; referred pain; hyperalgesia; experimental pain; central hypersensitivity; human experimental pain

Outcome Measures

Primary Outcomes (1)

• Intensity of shoulder pain on numeric rating scale

  two hours

Secondary Outcomes (2)

• Pressure pain thresholds

  two hours

• Area of referred pain

  two hours

Study Arms (3)

Part 1

EXPERIMENTAL

Intramuscular injection of capsaicin for the study of pain and hyperalgesia

Procedure: Intramuscular capsaicin injection

Part 2

ACTIVE COMPARATOR

Pain arising from supraspinatus muscle vs. pain arising from trapezius muscle. Nerve block is only expected to be effective in the former.

Procedure: Suprascapular nerve block

Part 3

ACTIVE COMPARATOR

Suprascapular nerve block vs. intramuscular local anesthetic against pain arising from the supraspinatus muscle.

Procedure: Local anesthetic infiltration

Interventions

Intramuscular capsaicin injection PROCEDURE

Intramuscular injection of capsaicin: 50 mcg/0.5 ml

Part 1

Suprascapular nerve block PROCEDURE

Injection of capsaicin 50 mcg/0.5 ml into the supraspinatus or trapezius muscle in randomized order, followed by suprascapular nerve block (ultrasound-guided) using Lidocaine 1%; nerve block is expected to be effective only in pain arising from the supraspinatus muscle. Trapezius pain serves as control condition. Evaluates the diagnostic validity of suprascapular nerve block for muscle pain.

Part 2

Local anesthetic infiltration PROCEDURE

Injection of capsaicin 50 mcg/0.5 ml into the supraspinatus muscle in two different sessions; suprascapular nerve block in one session and intramuscular local anesthetic infiltration in one session (in randomized order) using Lidocaine 1%; the aim is to investigate which procedure provides faster and more efficient pain relief. Compares effectivity of suprascapular nerve block vs. intramuscular local anesthetic infiltration.

Part 3

Eligibility Criteria

• Age: 18 Years - 80 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Age 18-80 years
• Written informed consent

You may not qualify if:

• Any acute pain at the moment of testing
• Intake of analgesics 24hours before testing
• Intake of antidepressants, anticonvulsants or benzodiazepines
• Allergy to local anesthetic or skin disinfectant
• Pregnancy or breast-feeding

Sponsors & Collaborators

• Insel Gruppe AG, University Hospital Bern: lead
• Aalborg University: collaborator

Study Sites (1)

University Department of Anesthesiology and Pain Therapy,Inselspital Bern

Bern, Canton of Bern, 3010, Switzerland

Location

Related Publications (3)

• Graven-Nielsen T, Gibson SJ, Laursen RJ, Svensson P, Arendt-Nielsen L. Opioid-insensitive hypoalgesia to mechanical stimuli at sites ipsilateral and contralateral to experimental muscle pain in human volunteers. Exp Brain Res. 2002 Sep;146(2):213-22. doi: 10.1007/s00221-002-1169-7. Epub 2002 Jul 13.

  PMID: 12195523 BACKGROUND

• Witting N, Svensson P, Gottrup H, Arendt-Nielsen L, Jensen TS. Intramuscular and intradermal injection of capsaicin: a comparison of local and referred pain. Pain. 2000 Feb;84(2-3):407-12. doi: 10.1016/s0304-3959(99)00231-6.

  PMID: 10666547 BACKGROUND

• Siegenthaler A, Moriggl B, Mlekusch S, Schliessbach J, Haug M, Curatolo M, Eichenberger U. Ultrasound-guided suprascapular nerve block, description of a novel supraclavicular approach. Reg Anesth Pain Med. 2012 May-Jun;37(3):325-8. doi: 10.1097/AAP.0b013e3182409168.

  PMID: 22222688 BACKGROUND

MeSH Terms

Conditions

Musculoskeletal Pain; Pain, Referred; Hyperalgesia

Condition Hierarchy (Ancestors)

Muscular Diseases; Musculoskeletal Diseases; Pain; Neurologic Manifestations; Signs and Symptoms; Pathological Conditions, Signs and Symptoms; Somatosensory Disorders; Sensation Disorders; Nervous System Diseases

Study Officials

• Michele Curatolo, M.D., Ph.D.

  Department of Anesthesiology and Pain Therapy, University of Washington, Seattle WA, USA

  STUDY CHAIR

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: SINGLE
• Who Masked: PARTICIPANT
• Purpose: BASIC SCIENCE
• Intervention Model: CROSSOVER
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: February 11, 2015
• First Posted: March 3, 2015
• Study Start: September 1, 2014
• Primary Completion: December 1, 2016
• Study Completion: December 1, 2016
• Last Updated: January 18, 2017

Record last verified: 2017-01

Locations

CH (1)