Transcutaneous Electrical Nerve Stimulation (TENS) operates on the principles of pain modulation through both peripheral and central mechanisms. By delivering low-voltage electrical impulses via electrodes placed on the skin, TENS activates large myelinated A-beta fibers, which inhibit the transmission of nociceptive signals through the dorsal horn of the spinal cord, a phenomenon described by the gate control theory.
Furthermore, TENS may induce the release of endogenous opioids, such as endorphins and enkephalins, which further attenuate pain perception by binding to opioid receptors in both the central and peripheral nervous systems. The immediate analgesic effects can manifest within 10 to 30 minutes after initiation of stimulation.
Quantitatively, clinical trials have demonstrated that TENS can lead to a statistically significant reduction in VAS scores, typically between 4 and 6 points, although variations depend on individual pain thresholds, the specific pain condition being treated, electrode placement, and the parameters of stimulation (e.g., frequency and intensity). Some studies suggest that higher frequencies (e.g., 80-100 Hz) may be more effective for acute pain management, whereas lower frequencies (e.g., 1-10 Hz) may provide longer-lasting effects.
Overall, TENS represents a non-invasive adjunctive therapy in acute pain management, offering a favorable benefit-to-risk ratio while minimizing the reliance on pharmacological interventions.
Post time: Apr-07-2025
