Motor cortex stimulation for chronic neuropathic pain: a preliminary study of 10 cases

There is growing evidence to support the use of motor cortex stimulation (MCS) in the management of patients with chronic neuropathic pain. A prospective audit of ten patients using a modified staged technique for motor cortex implantation provides further evidence for the analgesic effectiveness of this technique. Ten patients suffering from phantom limb pain (n=3), post stroke pain (n=5), post traumatic neuralgia secondary to gunshot injury to the brain stem (n=1) and brachyalgia secondary to neuro-fibromatosis (n=150% pain relief) and long-term benefit in 4/5 of patients who initially responded to intermittent cortical stimulation (longest follow up 31 months after implantation). Of those patients who benefited two had post stroke pain, two phantom limb pain and one post-traumatic neuralgia. We conclude that motor cortex stimulation is an effective analgesic intervention in some patients with chronic neuropathic pain, but it is difficult if not impossible to predict those patients who may respond to treatment prior to implantation. Randomised controlled trials are now urgently needed to test the effectiveness of motor cortex stimulation under double-blind conditions.