Background
Myokymia, a form of involuntary muscular movement, usually can be visualized on the skin as vermicular or continuous rippling movements.
The word myokymia was used first more than 100 years ago, when Schultze described continuous, slow, undulating muscular contractions in small muscles of hands and feet.
Kny used the term myoclonus fibrillaris multiplex to describe similar clinical manifestations.
For the past century, different authors applied the term myokymia to different involuntary muscular movements. Most of them showed electromyographic (EMG) evidence of spontaneous group discharges. This led to tremendous confusion in conceptually defining this particular clinical entity and its electrophysiologic features.