Advances in electrical nerve stimulation techniques to manage chronic pain: an overview.

Pharmacologic treatments to manage chronic intractable pain have long been sought. Neuropathic pain is usually resistant to analgesics. At present, no analgesic drug totally relieves pain without producing significant unwanted side effects. Electrical stimulation can offer a degree of relief to some sufferers without risk. Transcutaneous electrical nerve stimulation (TENS) has a long clinical history. Stimulation parameters have been studied to improve the efficacy of this method. TENS is inadequate for extensive and bilateral pain, and epidural spinal cord stimulation is indicated. Dorsal column stimulation (DCS) initially was used to manage pain, but recent clinical reports show that it also can be effective in vascular disease and movement disorders. This review article reports on improvements in the electrical parameters used in neurostimulation and advances in research to overcome methodologic problems of DCS.