Single fiber EMG, macro EMG, and scanning EMG. New ways of looking at the motor unit.

This review of different EMG techniques has pointed to their value in studies of the normal and abnormal motor unit. It also shows that the combination of techniques gives more information than each of them alone. This approach makes possible a description of the microphysiology and anatomical arrangement of muscle fibers in a motor unit, as well as the motor unit size. Electrophysiological tests can also describe the physiological status of the motor unit in more detail than previously. It is hoped that these methods will help in the study of normal motor unit in man, will guide the physician to arrive at a diagnosis, and that they may further the understanding of pathophysiological processes in neuromuscular disorders.