Single fiber EMG reference values: A collaborative effort

Single fiber electromyography (SFEMG) measurements of fiber density and jitter are used in the diagnosis of a variety of peripheral nervous system disorders. However, the normal values of these measurements for most muscles and age groups are not well documented in the literature. We present a retrospective and prospective multicenter collection of SFEMG jitter and fiber density data from control subjects obtained for the purpose of defining reference values for many muscles and different ages. The data and calculated upper limits for fiber density, individual pair jitter, and mean jitter are presented for each muscle in tabular and graphical format, for different age groups.