Clinical applications of high-density EMG

With the development of high-density, multichannel sEMG it becomes possible to measure single motor unit action potentials using the spatial information. Using the unique patterns of spatial spread of MUPs over the skin (MU fingerprint), MU classification and the determination of firing moments is done noninvasively. The endplate zone, depth, size, and position of MUs can be estimated. The use of muscle fiber conduction velocity measurements in channelopathies and the changes in pathological fatigue are described. Clinical applications of high-density sEMG measurements are reviewed. Examples of its use in motor unit number estimation and the analysis of fasculation potentials are provided.