Recent advances in neurostimulation analgesia

Over the last 30 years, neurostimulation has grown to include a number of central and peripheral applications. These now include the placement of epidural, extremity, deep brain, cortical, functional, and vagus nerve stimulators. Clinical conditions presently treated include neuropathic pain (failed back surgery syndrome; radiculopathy; chronic regional pain syndrome); ischemic pain (peripheral vascular disease, angina); tremor (Parkinson's); functional disorders (bladder dysfunction/urge incontinence); peripheral nerve injury; and seizure. Despite this diversity, more than 85% of all stimulators are still implanted epidurally over the spinal cord or via open peripheral extremity approaches for neuropathic pain. To date, this indication and these approaches have been associated with limited long-term success. However, a combination of recently developed electrode programming and positioning methodologies hold promise in improving these long-term outcomes, as well as in increasing the number of pain conditions amenable to neurostimulation therapy. This article reviews the historical basis and evolution of these methodologies and how they represent recent advances in neurostimulation.