[Electrodiagnosis, EMG, ENMG...: what do the future and the past tell us about the present?]

Neuromuscular imagery (NMI) of the future significantly extends the possibilities of nerve and muscle disorders investigation. It emphasizes some technical limitations inherent to electroneuromyography (ENMG) at the beginning of the 21st century, but also shows some progress that could have already been made to improve the quality of examination, as well as its comfort. In return, the history of these techniques points out a misunderstanding, by which electrodiagnosis and functional NMI have been asked to show morphological lesions, whereas their basic role is to highlight functional abnormalities that could account for patient complaints. Analysis of some frequent misinterpretations indicates that the functional point of view of ENMG and NMI requires to follow a suitable terminology, related to the anatomo-clinic one, but distinct from it. On the other hand, the example of purely functional abnormalities, like neuromuscular block, nerve conduction block and muscle excitability block, suggests that all electrophysiological abnormalities should be understood as membrane dysfunctions, before wondering whether they occur alone or accompanied with histological lesions. According to this specific point of view, the missions of present ENMG and future NMI are firstly to give patients an explanation of their complaints in terms of functional abnormalities, and secondly to try to bind these abnormalities to pathophysiological mechanisms defined at an anatomic level or at a molecular level.