Motor cortex stimulation and pain surgery

Neuropathic pain is considered a difficult to treat clinical condition and related to a large variety of lesions in the peripheral and/or central nervous system. Only approximately one-third of patients reach satisfactory relief with antiepileptic and antidepressants, which are considered mainstay treatments. Neurostimulation represent a major step forward in the treatment of intractable chronic pain. Chronic spinal cord stimulation allows pain control of mainly secondary to incomplete peripheral nerve damage. Deep brain stimulation of the sensory thalamic nuclei has been disappointing in the long term. Cortex motor stimulation was proposed as one alternative. It is an image guided surgery, improved by intra-operating electrophysiogical monitoring. The objective is to accurately locate the motor cortex target to be stimulated according to pain topography. In some types of central pain, such as thalamic pain, motor cortex stimulation constitutes a first intention therapeutic alternative. The same holds true for chronic facial neuropathic pain. Other indications need to be confirmed even when lasting efficacy has been reported in indications such as plexus brachial avulsion, phantom limb pain or post-paraplegic pain. Multicentric and randomized on/off studies are on the way