myoclonic jerk
Meaning of myoclonic jerk: A myoclonic jerk can occur normally, such as while falling asleep, or as a sign of an underlying neurological condition.
Definition of myoclonic jerk
A myoclonic jerk is a sudden, brief, involuntary contraction of a muscle or group of muscles, producing a quick, uncontrollable movement. It can involve a single muscle, causing a small, localized twitch, or a larger group of muscles, producing a more noticeable jerking movement of a limb or the whole body.
Myoclonic jerks occur commonly and normally in certain situations, such as the brief muscle jerk many people experience while falling asleep, known as a hypnic jerk, or hiccups, which represent a form of myoclonus affecting the diaphragm.
Myoclonic jerks can also occur as part of certain seizure disorders or other neurological conditions, in which case they may happen repeatedly or in clusters, and distinguishing this kind of myoclonic jerk from the common, benign form generally depends on its frequency, pattern, and whether other neurological symptoms accompany it.
Also known as
Used in a sentence
The patient described occasional myoclonic jerks affecting the arm, prompting further neurological evaluation.
Good to know
A myoclonic jerk occurring occasionally while falling asleep is a common, benign phenomenon, distinct from repeated or clustered myoclonic jerks that can occur as a feature of certain seizure disorders.
Word origin
Where “myoclonic jerk” comes from
Formed from Greek mys, meaning muscle, and klonos, meaning turmoil or violent motion.