Influence of Percutaneous Electrolysis on Endogenous Pain Modulation

Study Overview
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Brief Summary
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Percutaneous electrolysis is a minimally invasive approach that consists in the application of a galvanic current through an acupuncture needle. Although several mechanisms and effects are attributed to percutaneous electrolysis, currently there are only a few publications that delve into this topic. The aim of this study is to investigate the influence of percutaneous electrolysis on the endogenous pain modulation. Four groups of intervention will be involved: no-intervention, isolated needling procedure, low intensity percutaneous electrolysis and high intensity percutaneous electrolysis. The effects on the pain modulation system will be evaluated before and immediately after the intervention, through pressure pain thresholds, conditioned pain modulation and temporal summation.

Official Title
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Influence of Percutaneous Electrolysis on Endogenous Pain Modulation: A Randomized Clinical Trial

Conditions
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Pain

Intervention / Treatment
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* Procedure: Isolated needling procedure
* Procedure: Low intensity percutaneous electrolysis
* Procedure: High intensity percutaneous electrolysis


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Healthy asymptomatic subjects Aged 18 to 40 years Both genders Exclusion Criteria: Belonephobia or fear of needles Neurological, cardiovascular or metabolic diseases Any pathology or process that causes pain Cutaneous alterations Pregnancy Cognitive and sensitivity disorders Fibromyalgia Frequent or recent (24 hours before) intake of alcohol and other drugs Have received pharmacological, physiotherapeutic or other treatment in the last week Intake of caffeine in the two hours prior to measurement Vigorous physical activity on the day of testing

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 40 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Basic Science
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Sham Comparator: Needling Group<br>The needle will be inserted for 90 seconds without galvanic current. | Procedure: Isolated needling procedure<br>* The needle will be inserted into the common extensor tendon of the epicondyle (dominant elbow) for 90 seconds without galvanic current.<br>|
| Experimental: Low intensity percutaneous electrolysis<br>A single impact of galvanic current will be applied with an intensity of 0.3 mA for 90 seconds. | Procedure: Low intensity percutaneous electrolysis<br>* Once the needle is located in the common extensor tendon of the epicondyle (dominant elbow), a single impact of galvanic current will be applied with an intensity of 0.3 mA for 90 seconds.<br>|
| Experimental: High intensity percutaneous electrolysis<br>Three impacts of galvanic current will be applied with an intensity of 3 mA and a duration of 3 seconds each. | Procedure: High intensity percutaneous electrolysis<br>* The needle will be inserted in the target position during the same time as in the other groups (90 seconds). During the first stage of intervention the needle will be imbedded without galvanic current and when the end of the application time approaches (approximately 75 seconds) three impacts of galvanic current will be applied with an intensity of 3 mA and a duration of 3 seconds each.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change from baseline Conditioned Pain Modulation (evaluated by pressure algometry) immediately after the intervention | Assessed by algometry. Conditioning stimulus: pressure cuff on the arm. Measured at three locations (bilaterally): common extensor tendon of the epicondyle, cervical spine and tibialis anterior muscle. | Baseline and immediately after the intervention | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change from baseline Pressure Pain Thresholds immediately after the intervention | Assessed by algometry. Measured at three locations (bilaterally): common extensor tendon of the epicondyle, cervical spine and tibialis anterior muscle. | Baseline and immediately after the intervention | 
| Change from baseline Temporal Summation (evaluated by VNRS) immediately after the intervention | Assessed by Verbal Numeric Rating Scale (11-point). Temporary stimuli: 10 consecutive pressures with the algometer at the intensity of the pressure pain threshold. Three locations (bilaterally): common extensor tendon of the epicondyle, cervical spine and tibialis anterior muscle. | Baseline and immediately after the intervention | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Electric Stimulation Therapy, Randomized Clinical Trial, Interventional Ultrasonography, Percutaneous Electrolysis, Endogenous Pain Modulation, Pain, Conditioned Pain Modulation, Sensory Thresholds