Unmodulated 5 Kilohertz Currents Versus TENS: Effect on Pain Thresholds, Tactile Threshold, and Nerve Conduction

Unmodulated 5 Kilohertz Alternating Currents Versus TENS: Effect on Mechanical and Thermal Pain Thresholds, Tactile Threshold, and Peripheral Nerve Conduction in Humans.

The purpose of this study is to determine whether the transcutaneous application of unmodulated 5 Kilohertz (KHz) alternating currents are effective in decreasing the thermal and mechanical experimental pain and cause changes in peripheral nerve conduction. Moreover evidence whether the effect and comfort of this current is greater than Conventional TENS (Transcutaneous Electrical Nerve Stimulation) commonly used for the treatment of clinical pain.

In the last years several animal experimental studies have evidenced that high frequency unmodulated currents about 5 KHz can cause a peripheral nerve block. However electric currents with these high frequencies that are usually used for the treatment of pain in humans are interrupted or modulated (i.e. interferential currents)

This evidences in animals could have application in pain treatment, characterized by overactive nervous system. For this reason it was decided to compare the effects on experimental pain and peripheral nerve conduction of this new electric current versus sham stimulation and TENS (Transcutaneous Electrical Nerve Stimulation).

The scientific literature on transcutaneous electrical stimulation in humans and changes in nerve conduction and / or somatosensory thresholds focuses mainly on TENS (Transcutaneous Electrical Nerve Stimulation). Therefore TENS is a good reference standard to compare the effect of this new currents.

Inclusion Criteria:

• Participants will be volunteer healthy students of Physiotherapy, University of Castilla - La Mancha, older than 18 years.

Exclusion Criteria:

• Neuromuscular disease.
• Epilepsy.
• Trauma, surgery or pain affecting the upper limb, shoulder girdle or cervical area.
• 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.
• Sensitivity disturbance in upper limb.