Etymed
myoclonus
Definition
A sudden, involuntary muscle contraction or jerk
Clinical context
A 35-year-old patient presents to the emergency department complaining of sudden, jerky movements that occur primarily during sleep and upon awakening. The patient reports these episodes have been increasing in frequency over the past few weeks and are disrupting their sleep pattern. On examination, the physician observes brief, shock-like muscle contractions in the arms and legs when startled.
Mnemonic
Myoclonus = Myos (muscle) + clonus (jerking), remember 'MUSCLE JERK' for sudden involuntary muscle contractions