Transcutaneous electrical nerve stimulation (TENS) is a form of electrical physical therapy that has been used in the treatment of pain since the early 1970s. Pads are placed on the skin and a mild electrical current is sent through to block pain sensations. Many TENS units are small, portable, and may be hidden under clothing. A review of the first ten years of research on TENS described success rates in treating chronic pain varying from 12.5% to 92% after one year of treatment.9 Variations in success rates were attributed to differences in the type of pain the TENS was treating. More current research identifies specific conditions that consistently respond well to TENS therapy:10, 11rheumatoid arthritis, osteoarthritis, low back pain, phantom limb pain, and post-herpetic nerve pain (shingles). Pain caused by pinched nerves in the spine responds poorly to TENS therapy. While a small number of controlled trials have reported no benefit,12, 13 most evidence suggests TENS is an effective form of therapy for many types of pain.14, 15, 16
Relaxation exercises may decrease the perception of pain. Pain increases as anxiety increases; using methods to decrease anxiety may help reduce pain.17 In one controlled hospital study, people who were taught mind-body relaxation techniques reported less pain, less difficulty sleeping, and fewer symptoms of depression or anxiety than did people who were not taught the techniques.18
Acupuncture has been shown to decrease pain by acting on the enkephalin-based, pain-killing pathways.19 In 1997, the National Institutes of Health (NIH) stated that acupuncture is useful for muscular, skeletal, and generalized pain, as well as for anesthesia and post-operative pain. The NIH statement was based on a critical review of over 67 controlled trials of acupuncture for pain control.
Practitioners of manipulation report that it often produces immediate pain relief either in the area manipulated or elsewhere.20 Controlled trials have found that people given spinal manipulation may experience reduction in pain sensitivity of the skin in related areas,21, 22 a reduction in joint and muscle tenderness in the area manipulated,23 and a decrease in elbow tenderness when the neck was manipulated.24 One study showed no effect of lower spine manipulation on sensitivity to deep pressure over low back muscles and ligaments.25 Some researchers have speculated that joint manipulation affects pain by enhancing the effects of endorphins. However, only one26 of three27, 28 controlled studies has shown an effect of manipulation on endorphin levels.
Hypnosis has been shown to significantly reduce pain associated with office surgical procedures that are performed while the patient is conscious (i.e., without general anesthesia).29 People undergoing office surgical procedures received standard care, structured attention or self-hypnotic relaxation in one study. Those using self-hypnosis had no increases in pain during the procedures, compared to those in the other groups. Hypnosis also appeared to stabilize bleeding, decrease the requirement for narcotic pain drugs during the procedure, and shorten procedure time.