asterixis

asterixis

 [as″ter-ik´sis]

a motor disturbance marked by intermittent lapses of an assumed posture as a result of intermittency of sustained contraction of groups of muscles; called liver flap because of its occurrence in coma associated with liver disease, but also observed in other conditions.

 To elicit asterixis (flapping tremor) the patient extends the arm, dorsiflexes the wrist, and extends the fingers. The hand is observed for rapid, nonrhythmic extensions and flexions. From Ignatavicius and Workman, 2002.

as·ter·ix·is

(as'ter-ik'sis),

Involuntary jerking movements, especially in the hands, best elicited by having the patient extend the upper limb, dorsiflex the wrists, and spread the fingers; results from lapses of sustained posture; seen primarily with various metabolic and toxic encephalopathies, especially hepatic encephalopathy.

Synonym(s): flapping tremor

[G. a- priv. + stērixis, fixed position]

asterixis

/as·ter·ix·is/ (as″ter-ik´sis) a motor disturbance marked by intermittent lapses of an assumed posture as a result of intermittency of sustained contraction of groups of muscles; called liver flap because of its occurrence in hepatic coma, but observed also in other conditions.

asterixis

[as′tərik′sis]

Etymology: Gk, a, sterixis, not fixed position

a hand-flapping tremor, often accompanying metabolic disorders. The tremor is usually induced by extending the arm and dorsiflexing the wrist. Asterixis is seen frequently in hepatic encephalopathy. Also called flapping tremor, liver flap.

Hepatology An involuntary jerking tremor of wide amplitude elicited upon dorsiflexion of the pronated wrist and spreading of extended fingers; in full-blown flapping tremors, there is abrupt flexion of the fingers at the metacarpophalangeal joint and flexion of the wrist, occurring asynchronously with each other every few seconds, due to exaggerated reflexes; bilateral flapping tremor is quasi-pathognomonic for metabolic, often alcohol-related, hepatic encephalopathy seen in end-stage—post-fibrotic—cirrhosis due to increased blood ammonia
Neonatology Coarse bilateral tremors, accompanied by limb rigidity, hyperreflexia, resistance to flexion and extension, seen in infants born to heroin-addicted mothers who undergo ‘withdrawal’ at birth

asterixis

Flapping tremor Neurology An exaggerated muscle tremor characterized by involuntary jerking of the hand in flexion and extension, classically seen in advanced liver disease and hepatic encephalopathy.

as·ter·ix·is

(as-tĕr-ik'sis)

Involuntary jerking movements, especially in the hands, due to arrhythmic lapses of sustained posture; seen primarily with metabolic and toxic encephalopathies, especially hepatic encephalopathy.
Synonym(s): flapping tremor.

[G. a- priv. + stērixis, fixed position]

asterixis

A recurrent flapping tremor of the arms, like the action of a bird's wings. Asterixis is characteristic of the brain disorder associated with liver failure—hepatic encephalopathy.