Percutaneous electrical nerve stimulation (PENS) involves simultaneous electro-acupuncture using low to high frequencies (2-30-hertz range) using pin electrodes inserted just below the skin for the purpose of chronic musculoskeletal pain management, used to relieve chronic intractable pain, post-surgical pain and pain associated with traumatic injuries unresponsive to other standard pain therapies. .
Pin electrodes are inserted either around or immediately adjacent to the nerves bilaterally serving the painful area by stimulating pain modulator neurotransmitters. PENS is generally reserved for patients who fail to get pain relief from TENS possibly due to physical barriers (e.g., scar tissue, obesity) to the conduction of electrical stimulus.. The mechanism of action is unknown, but it is purported that the electrical pulses block the transmission of pain to nerve fibers or may stimulate the release of natural endorphins or serotonin.
Treatment regimens consist of 20-30-minute sessions, once or twice a week for 8 to 10 sessions. Treatments side affects are minimal but increased pain and tenderness post treatment is possible