The surface electromyogram (EMG) is used to infer the neural drive sent by the central nervous system to the muscles by associating its amplitude to the strength of the neural activation. In addition, the surface EMG is adopted in the design of technologies for motor rehabilitation with the aim to restore the lost limb functionality of amputees. In this perspective, it is possible to translate this biologic signal into commands for controlling intuitively the prosthetic device. Since the surface EMG amplitude constitutes a poor indicator of the neural information, more advanced methods were developed such as the high-density surface EMG signal decomposition.