A syndrome characterized by myokymia, myotonia, muscular wasting and increased perspiration.

TLDR: Electromyography shows repetitive usually normal action potentials corresponding to one or several units in each contracting part of muscles, which means that myokymia is produced by brief tetanic contractions2 in contrast to fasciculations, which are rapid twitches, accompanied by single, often large and polyphasicaction potentials.

Abstract: The term myokymia, which was introduced by Schultze (1895)l , is used to designate different syndromes. This has resulted in some confusion. The term should be reserved for spontaneous, relatively slow movements of parts of muscles. Different muscle regions move independently. giving the muscle surface an undulating appearance. Electromyography shows repetitive usually normal action potentials corresponding to one or several units in each contracting part. This means that myokymia is produced by brief tetanic contractions2 in contrast to fasciculations, which are rapid twitches, accompanied by single, often large and polyphasic action potentials. hlyokymia and fasciculation should not be confused with the quivering or flickering movements normally accurring in part of a muscle, which are known as “live flesh” and can be considered as a type of inyoclonias. Such movements are composed of a series of twitches, each corresponding to one large action potential. The series of twitches and concomitant potentials recur after intervals of wrying length in a stereotype way. The same muscle region is the site of such movements usually during a few days. Both these and other types of spontaneous muscle contractions have been designated as niyokymia in the literature. In some descriptions antedating the introduction of electromgography it is difficult to decide what type of movement is to be understood by the term myokymia. Generalized myokymin is rare and only few reports of it are on record ( 3 , 4 , 5, 6, i ) . I t is often combined with excessive sweating (3,1), and occasionally also with myotonia ( 5. 6. 7 ) .