Effectiveness and Safety of Electrical Stimulation With Alternating High-frequency Currents (30-50 Kilohertz) on the Sensorimotor System in Healthy Volunteer Subjects
Overview
- Phase
- Not Applicable
- Intervention
- Not specified
- Conditions
- Healthy
- Sponsor
- University of Castilla-La Mancha
- Enrollment
- 34
- Locations
- 1
- Primary Endpoint
- Pressure pain threshold
- Last Updated
- 3 years ago
Overview
Brief Summary
High-frequency alternating current (HFAC) stimulation (between 1 kilohertz (kHz) and 100 kHz) on the peripheral nerve has been shown in basic animal research to produce a rapidly reversible nerve block without nerve damage. In human studies, frequencies between 1 kHz and 30 kHz had been applied (both transcutaneously and percutaneously), showing rapidly reversible sensorimotor changes after stimulation without adverse effects. However, the effect of currents with a frequency higher than 30 kHz, which has been shown to be more effective in eliciting nerve block in primates, has not been investigated in humans.
The main objective of this study is to investigate the safety of the intervention and the effect in healthy volunteers of transcutaneous application of alternating currents with frequencies between 30 kHz and 50 kHz on neurophysiological changes in the nerve (nerve conduction velocity and antidromic sensory action potentials (SNAPs), sensory (pain to pressure, epicritic sensitivity and thermal pain to heat) and motor (maximal isometric force) components of the median nerve.
Detailed Description
Electrical stimulation with high-frequency alternating currents (between 1 kHz and 100 kHz) on the peripheral nerve has shown, in basic research with animals, that it produces a rapidly reversible nerve block without causing damage to the nerve. In humans, studies have been carried out with frequencies between 1 kHz and 30 kHz applied both transcutaneously and percutaneously, showing rapidly reversible sensorimotor changes after stimulation and without causing adverse effects. However, the effect of currents with a frequency greater than 30 kHz has not been investigated in humans, which has been shown to be more effective in causing nerve block in primates. The main objective of this study is to investigate the safety of the intervention and the effect in healthy volunteers of the transcutaneous application of alternating currents with frequencies between 30 kHz and 50 kHz on neurophysiological changes in the nerve (nerve conduction velocity and antidromic sensory compound action potentials (PACSA), the sensitive component (pressure pain, epicritic sensitivity and thermal pain to heat) and motor (maximum force) of the median nerve. A randomized, double-blind, placebo-controlled crossover clinical trial has been designed. The participants will be healthy volunteers between 18 and 40 years old recruited from the students and staff of the Faculty of Physiotherapy and Nursing of the University of Castilla-La Mancha. Four interventions will be performed randomizing the order: Group A: 30 kHz, group B: 40 kHz, group C: 50 kHz and group D: sham electrical stimulation.
Investigators
Eligibility Criteria
Inclusion Criteria
- •Healthy volunteer participants.
- •Ability to perform all clinical tests and understand the study protocol, as well as obtain informed consent.
- •Tolerance to the application of electrotherapy.
Exclusion Criteria
- •Having been treated with an electric current similar to the one applied prior to the intervention.
- •Neurological pathology of peripheral or central origin.
- •Altered sensitivity in the area of application of the intervention.
- •No compromise of continuity.
- •History of neuromuscular disease.
- •Epilepsy.
- •Trauma, surgery or pain affecting the upper limb.
- •Diabetes.
- •History of cancer.
- •Cardiovascular, metabolic or immunological diseases.
Outcomes
Primary Outcomes
Pressure pain threshold
Time Frame: Baseline, during intervention at 10 minutes, post immediate at 15 minutes and 15 minutes post intervention.
It will be assessed as an indirect measure of the blockade of the Aδ sensory fibers of the median nerve. Once the applicator is placed perpendicular to the skin, over an uncomfortable spot on the palmar aspect of the non-dominant hand, the pressure shall be increased at a rate of approximately 5 N/s. Three measurements shall be taken with an interval between measurements of 15 seconds, the average of the three measurements shall be taken as the pressure pain threshold.
Secondary Outcomes
- Maximal isometric pinch strength(Baseline, during intervention at 10 minutes, post immediate at 15 minutes and 15 minutes post intervention.)
- Skin temperature(Baseline, during intervention at 10 minutes, post immediate at 15 minutes and 15 minutes post intervention.)
- Compound antidromic sensitive nerve action potentials(Baseline, during intervention at 10 minutes, post immediate at 15 minutes and 15 minutes post intervention.)
- Two points discrimination threshold(Baseline, during intervention at 10 minutes, post immediate at 15 minutes and 15 minutes post intervention.)
- Adverse effects and subjective current sensations(Post immediate at 15 minutes and 24 hours after the intervention)
- Heat pain threshold(Baseline, during intervention at 10 minutes, post immediate at 15 minutes and 15 minutes post intervention.)
- Outcome and participant blinding assessment(Post immediate at 15 minutes each intervention.)