Electrical Stimulation, Neuromodulation
Conditions
Keywords
High-frequency alternating current, nerve block, somatosensory threshold, motor threshold, percutaneous electrical stimulation
Brief summary
High-frequency alternating currents of greater than 1 kHz applied on peripheral nerves has been used in animal studies to produce a motor nerve block. It has been evidenced that frequencies higher than 5 kHz are necessary to produce a complete peripheral nerve block in primates, whose nerve thickness is more similar to humans.
Detailed description
The previous studies with transcutaneous and percutaneous HFAC, suggest high-frequency stimulation (10 and 20 kHz) have an inhibitory effect over muscle strength and somatosensory threshold. However, the 30 kHz frequency has never been applied, and the hypothesis is that it can produce a greater blockage at the sensitive level and be a more comfortable application for the patient. The purpose of the present work is to determine if a greater blockage of the sensory component of the nerve occurs with this frequency and is to reduce the amount of current intensity needed using a percutaneous approach by apply two acupuncture needles near the nerve as electrodes.
Interventions
DEVICE30 kHz stimulation (Myomed 932, Enraf-Nonius)
A charge-balanced, symmetric, biphasic sinusoidal current without modulation will be delivered at a frequency of 30 kHz. The stimulation intensity will be defined as that sufficient to produce a strong but comfortable sensation, just below motor threshold, over the median nerve through the electrotherapy device Myomed 932. (Enraf-Nonius, Delft,Netherlands)
Sham stimulation will be delivered at a frequency of 30 kHz only during the first 30 seconds.
Sponsors
University of Castilla-La Mancha
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
DOUBLE (Subject, Outcomes Assessor)
Eligibility
Sex/Gender
ALL
Age
18 Years to 60 Years
Healthy volunteers
Yes
Inclusion criteria
* Healthy volunteers * Ability to perform all clinical tests and understand the study process, as well as obtaining informed consent. * Tolerance to the application of electrotherapy. * That they have not diagnosed any pathology. * They do not present a contraindication to puncture and / or the application of electric currents.
Exclusion criteria
* Neuromuscular disease. * Epilepsy. * Trauma, surgery or pain affecting the upper limb * Osteosynthesis material in the upper limb. * Diabetes. * Cancer. * Cardiovascular disease. * Pacemaker or other implanted electrical device. * Take any drug (NSAIDs, corticosteroids, antidepressants, analgesics, antiepileptics, ...) during the study and in the previous 7 days. * Presence of tattoos or other external agent introduced into the treatment or assessment area. * Pregnancy
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Amplitude Antidromic median sensory nerve action potential | Immediately after treatment at 20 minutes | The recording electrodes were placed on the second finger and the stimulus will be applied on the median nerve (above the elbow joint). The stimulus will consist of a train of 10 pulses (100 μs width), applied at supramaximal stimulation, presented at 1 Hz (DS7A, Digitimer Ltd). Peak-to-peak amplitude (PPA) will be registered with a specific software (Signal software, CED) and will be expressed in millivolts. |
| Amplitude of Antidromic median sensory nerve action potential | Baseline at 0 minutes | The recording electrodes were placed on the second finger and the stimulus will be applied on the median nerve (above the elbow joint). The stimulus will consist of a train of 10 pulses (100 μs width), applied at supramaximal stimulation, presented at 1 Hz (DS7A, Digitimer Ltd). Peak-to-peak amplitude (PPA) will be registered with a specific software (Signal software, CED) and will be expressed in millivolts. |
| Tactile Threshold | Baseline at 0 minutes | The tactile threshold will be measured with Von Frey filaments and will be expressed in millinewton |
| Pressure Pain Threshold | Baseline at 0 minutes | The PPT will be measured with an algometer and will be expressed in Newtons |
| Muscle strength | Baseline at 0 minutes | Muscle strength will be measured with a dynamometer and will be expressed in Kgs. |
| Latency Antidromic median sensory nerve action potential | Immediately after treatment at 20 minutes | The recording electrodes were placed on the second finger and the stimulus will be applied on the median nerve (above the elbow joint). The stimulus will consist of a train of 10 pulses (100 μs width), applied at supramaximal stimulation, presented at 1 Hz (DS7A, Digitimer Ltd). Latency (NPL) will be registered with a specific software (Signal software, CED) and will be expressed in millisecond. |
| Latency of Antidromic median sensory nerve action potential | Baseline at 0 minutes | The recording electrodes were placed on the second finger and the stimulus will be applied on the median nerve (above the elbow joint). The stimulus will consist of a train of 10 pulses (100 μs width), applied at supramaximal stimulation, presented at 1 Hz (DS7A, Digitimer Ltd). Latency will be registered with a specific software (Signal software, CED) and will be expressed in millisecond. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Numerical Discomfort Rate Score | After the intervention at 35 minutes | the possible discomfort caused by the interventions will be assess by a numerical rate score. The NRS consists of a scale from 0 (no discomfort) to 10 (worst possible discomfort) |
| Numerical Pain Rate Score | After the intervention at 35 minutes | The NRS consists of a scale from 0 (no pain) to 10 (worst possible pain) |
| Number of participants with intervention-related adverse effects | After the intervention at 35 minutes | The possible adverse effects caused by the interventions will be assess by a closed questionnaire, where the presence of any adverse effect would be qualified as 1 point and the negative presence of adverse effect as 0 point. |
| Blinding success | After the intervention at 35 minutes | Blinding of subjects and researchers will be assessed using the Bang questionary. It will be the question after the intervention, What type of treatment do you think you have received? Will be asked, with 5 items: (1) I firmly believe that I have received an experimental treatment; (2) I slightly believe that I have received an experimental treatment; (3) I strongly believe that I have received a placebo; (4) I slightly think I have received a placebo; (5) Don't know, don't answer., Index where -1 is blinded and 1 is unblinded. |
| Baseline nerve temperature | Baseline at 0 minutes, at 15 minutes, immediately after treatment at 20 minutes, and immediately after treatment at 30 minutes | Nerve temperature will be measured using a termodoppler (Celsius degrees) |
Countries
Spain
Outcome results
None listed