Nuti C et al. (2005) Motor cortex stimulation for refractory neuropathic pain: four year outcome and predictors of efficacy. Pain 118: 43–52

There is some evidence that stimulation of the primary motor cortex can bring relief to patients with medically refractive neuropathic pain. Nuti and colleagues have carried out a prospective study to examine the long-term efficacy of this technique.

A total of 31 consecutive patients with neuropathic pain were recruited. Pain was a consequence of hemorrhagic or ischemic stroke in most cases, and all patients had failed to respond to conventional therapies. Each patient had a motor cortex stimulation device implanted under general anesthesia, with one or two electrodes positioned over the motor region corresponding to the pain.

During a mean postoperative follow-up period of 4 years, 3 patients (10%) experienced 'excellent' pain relief, whereas 13 (42%) reported that the results were 'good'. Pain relief was 'poor' or 'negligible' in the remaining 15 cases (48%). Approximately half of the patients decreased their use of analgesics after the surgery, and these drugs were stopped altogether in 11 cases (35%). Long-term pain relief was predicted by the degree of pain relief recorded in the first month after surgery.

These findings indicate that motor cortex stimulation can offer long-lasting relief of neuropathic pain in some patients. The authors state that further work in this area should include larger numbers of patients and should focus on improving patient selection.