Transcutaneous vs Percutaneous Electrical Stimulation of the Radial Nerve

Comparison of the Effects of Transcutaneous vs. Percutaneous Electrical Nerve Stimulation on the Sensorimotor System of the Radial Nerve in Healthy Volunteers

This study aims to compare the effects of two types of electrical nerve stimulation techniques-Transcutaneous Electrical Nerve Stimulation (TENS) and Percutaneous Electrical Nerve Stimulation (PENS)-on the sensory and motor components of the radial nerve in healthy volunteers.

Transcutaneous Electrical Nerve Stimulation (TENS) is a non-invasive, low-cost, and widely used electrotherapy technique that applies electrical currents through surface electrodes on the skin to relieve pain. Percutaneous Electrical Nerve Stimulation (PENS) is a minimally invasive technique that delivers the electrical current through fine needles inserted near a peripheral nerve, potentially producing stronger physiological effects.

In this randomized, double-blind controlled clinical trial, 120 healthy participants aged 18-60 years will be randomly assigned to one of four groups:

Transcutaneous Electrical Nerve Stimulation (TENS)

Percutaneous Electrical Nerve Stimulation (PENS)

Sham Transcutaneous Electrical Nerve Stimulation (TENS) (placebo)

Sham Percutaneous Electrical Nerve Stimulation (placebo)

Each participant will receive one 20-minute stimulation session. Outcomes will include:

Pressure pain threshold (PPT) (measured with an algometer),

Thermal pain threshold (measured with a thermode),

Maximal Isometric wrist extensor strength (measured with a hand-held dynamometer).

The goal is to determine whether Percutaneous Electrical Nerve Stimulation (PENS) produces greater changes in sensory and motor parameters than Transcutaneous Electrical Nerve Stimulation (TENS) and to evaluate differences compared to placebo. This research will improve understanding of the physiological effects of these commonly used electrotherapy modalities and support evidence-based decision-making in clinical practice.

Inclusion Criteria:

• Healthy volunteers aged between 18 and 60 years.
• No history of musculoskeletal or neurological disorders.
• No alterations in sensitivity in the upper limb.
• Not taking any medication in the previous two weeks.
• Able to understand the study procedures and provide informed consent.

Exclusion Criteria:

• Any neurological or neuromuscular disease.
• History of upper limb trauma, surgery, or persistent pain.
• Contraindications to electrical stimulation or invasive techniques.
• Presence of cardiac pacemaker, epilepsy, diabetes, cancer, or cardiovascular disease.
• Skin lesions or infections in the stimulation area.
• Pregnancy or suspected pregnancy.