Electrical stimulation in the treatment of pain.
OBJECTIVE
To review the published literature concerning the treatment of painful conditions using devices that deliver electrical stimulation to nervous structures. The review briefly surveys the results obtained using surface electrodes ("TENS") as well as implanted devices.


METHODS
The method used is a critical review of the important published literature up to mid-1999. References were obtained using Medline and the keywords "pain", together with "electrical", "stimulation", "neurostimulation" or "TENS".


RESULTS
Electrical stimulation has been found to be of potential benefit in the management of a range of painful conditions. Adequately controlled trials of electrical stimulation are often difficult to achieve. Implanted devices tend to be used in the more severe intractable pain conditions. It is likely that there is more than one mechanism of action. The mechanisms of action are however still often poorly understood, even though historically theoretical and experimental advances in the understanding of pain mechanisms prompted the development of clinical systems and the institution of clinical studies.


CONCLUSIONS
TENS has proved to be remarkably safe, and provides significant analgesia in about half of patients experiencing moderate predictable pain. Implanted devices can be more effective, but they carry a risk of device failure, implant infection or surgical complication, and are reserved for the more severe intractable chronic pains. The main implanted devices used clinically are the spinal cord stimulator and the deep brain stimulator.
Rushton
David N
DN
Frank Cooksey Rehabilitation Unit, King's College Hospital, Denmark Hill, London SE5 8AZ, UK. david.rushton@kingshc.nhs.uk
D000787:Angina Pectoris / Q000628:therapy; D004599:Electric Stimulation Therapy / Q000379:methods* / Q000592:standards; D004567:Electrodes, Implanted; D006801:Humans; D017116:Low Back Pain / Q000628:therapy; D009044:Motor Cortex / Q000503:physiopathology; D009422:Nervous System Diseases / Q000628:therapy; D010146:Pain / Q000503:physiopathology; D059408:Pain Management; D010149:Postoperative Pain / Q000628:therapy; D017933:Peripheral Nervous System / Q000503:physiopathology; D013116:Spinal Cord / Q000503:physiopathology; D004561:Transcutaneous Electric Nerve Stimulation