The current status of electrical stimulation of the nervous system for the relief of chronic pain

Neuroaugmentation techniques have been in common use for nearly 30 years. Spinal stimulation is the most important treatment mode for many patients with failed back syndrome. Stimulation can replace or supplement reoperation. Stimulation has been shown to be useful in many other chronic pain states and deserves wider application. However, it is not a technique to be used casually. Effective use requires a thorough understanding of the pain states to be treated, appreciation of the comorbidities that accompany chronic pain, an infrastructure to support the patient and the surgeon, and a dedication to lifelong care for the patient with the implant. All of these mean that patients are better handled by a few dedicated individuals than by wide dispersion of the technique among neurosurgeons who see only a few such patients each year. Peripheral nerve stimulation is very effective, but the number of potential candidates is small. Brain stimulation remains investigative and has not yet found a clearly defined place in pain management. If these techniques are to continue to evolve, more basic research on the mechanisms of action will be necessary if efficacy is to be improved. Most of the research to date has been in clinical efficacy. Defining the mechanisms of action will be the next important step.