Neuropathic Chronic Pain clinical trials

Analgesic Stimulation Non-invasive of the Motor Cortex

Prevalence of neuropathic pain raise to 6.9 % in the general population and can reach more than 58 % for patients that carry a lesion of the spinal cord. This pathological condition stays a major health problem, particularly as the efficacity of available treatments is currently limited. Only 30 to 40% of patients are relieved of more than 50% of their pain by a pharmacological approach. In case of failure, drug treatments or in addition of these ones, stimulation of the motor cortex is a therapeutic path proposed by Tsubokawa since the beginning of 1990s, but that found its place for neuropathic drug-resistant pain management only since a decade. Neurophysiologic mechanisms of the analgesic efficacity of the motor cortex stimulation are still little understood. This stimulation can be realised in a chronic and invasive way with implanted electrodes. This process allow a lasting relief for about half of operated persons, without the possibility to identify clinical selection criterion reliable for potentially responding patients for this technique. Recently, two electrophysiological non invasive techniques have been developed, allowing to get an analgesic stimulation of the motor cortex: the repetitive transcranial magnetic stimulation (rTMS) and the direct current transcranial magnetic stimulation (tDCS). The main goal of this study is to compare the importance of analgesic effect of tDCS in chronic drug-resistant neurophysiologic pains to the one get thanks to a reference method of stimulation non invasive of the motor cortex, the rTMS whose analgesic effect is already validated by data of the literature.