[Neurostimulation in the treatment of chronic pain]

Different types of neurostimulation are proposed essentially in cases of chronic neuropathic pain, non controlled by anticonvulsivants and antidepressants. The aim is usually to activate a failing inhibitory system, involved in the transmission and the modulation of the nociceptive stimulus. The site of stimulation (transcutaneous, spinal cord, thalamic) is choosen according to the severity of pain and especially the degree of lemniscal dysfunction evaluated by clinical and electrophysiological data. Transcutaneous electrical stimulation and spinal cord stimulation are efficient for neurogenic pain secondary to partial deafferentation. When dysfunction or lesion extend to the pre-ganglionic portion, it's preferable to propose stereotactic thalamic stimulation or central gyrus stimulation. The analgesic effect concerns permanent burning pain in the context of sensitive deafferentation: after distal nervous lesions, radicular, plexular or spinal lesions or after stroke with ischemic lesions along the nociceptive pathways. These different methods must only be proposed if there is a frequent clinical and technical monitoring.