Analgesic Mechanisms of Percutaneous Electrolysis

Study Overview
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Brief Summary
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Percutaneous electrolysis is based on the application of a galvanic current through an acupuncture needle. The underlying mechanisms that explain the efficacy of this technique are not completely well understood. The objective is to delve into the neurophysiological analgesic effects of percutaneous electrolysis. Participants will be assigned to one of three intervention groups. The analgesic effects of the technique will be evaluated by means of variables related to endogenous pain modulation.

Official Title
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Neurophysiological Effects of Percutaneous Electrolysis Related to Endogenous Pain Modulation

Conditions
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Percutaneous Electrolysis, Pain, Analgesia, Pain Modulation, Endogenous Analgesia System

Intervention / Treatment
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* Other: Sham intervention
* Other: Low intensity percutaneous electrolysis
* Other: High intensity percutaneous electrolysis


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Asymptomatic subjects Signature of the informed consent Exclusion Criteria: Fear of needles Any pathology or process that causes pain Neurological, rheumatologic, cardiovascular or metabolic diseases Cutaneous alterations and cognitive or sensitivity disorders Pregnancy Recent intake of alcohol or caffeine 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: Sham intervention<br>The needle will be inserted for 90 seconds without galvanic current. | Other: Sham intervention<br>* The needle will be inserted into the right common extensor tendon of the epicondyle for 90 seconds without galvanic current.<br>|
| Experimental: Low intensity percutaneous electrolysis<br>Galvanic current will be applied with an intensity of 0.3 mA for 90 seconds. | Other: Low intensity percutaneous electrolysis<br>* A single impact of galvanic current will be applied in the common extensor tendon of the epicondyle (right side) with an intensity of 0.3 mA for 90 seconds.<br>|
| Experimental: High intensity percutaneous electrolysis<br>Participants will receive three impacts of galvanic current with an intensity of 3 mA for 3 seconds each. | Other: High intensity percutaneous electrolysis<br>* Three impacts of galvanic current will be applied in the common extensor tendon of the epicondyle (right side) 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 |
| --- | --- | --- |
| Changes from baseline in Pressure Pain Thresholds (PPT) | PPTs will be measure by algometry in the common extensor tendon of the epicondyle, bicipital groove and tibialis anterior muscle (all of the right side). | Baseline and immediately after the intervention | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Changes from baseline in Conditioned Pain Modulation (CPM) | CPM will be assess by upper extremity submaximal effort tourniquet test with algometric measures in the common extensor tendon of the epicondyle, bicipital groove and tibialis anterior muscle (all of the right side). | Baseline and immediately after the intervention | 
| Changes from baseline in Temporal Summation (TS) | Assessed by Verbal Numeric Rating Scale (11-point). 10 consecutive pressures will be applied in the three previous locations (epicondyle, bicipital groove and tibialis anterior) with the algometer at the intensity of the pressure pain threshold | Baseline and immediately after the intervention |