Asterixis

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Asterixis
Classification and external resources
ICD-10 R27.8
ICD-9 781.3
DiseasesDB 33950
MeSH D020820

Asterixis (also called the flapping tremor, or liver flap) is a tremor of the hand when the wrist is extended, sometimes said to resemble a bird flapping its wings. This motor disorder is characterized by an inability to actively maintain a position, which is demonstrated by jerking movements of the outstretched hands when bent upward at the wrist. The tremor is caused by abnormal function of the diencephalic motor centers in the brain, which regulate the muscles involved in maintaining position. Asterixis is associated with various encephalopathies due especially to faulty metabolism.[1]The term derives from the Greek a, "not" and stērixis, "fixed position".

Associated conditions and presentation[edit]

Usually there are brief, arrhythmic interruptions of sustained voluntary muscle contraction causing brief lapses of posture, with a frequency of 3–5 Hz. It is bilateral, but may be asymmetric.

History[edit]

R.D. Adams and J.M. Foley first described asterixis in 1949 in patients with severe liver failure and encephalopathy.[3]

References[edit]

  1. ^ "Asterixis - Definition". Retrieved 6.1.2011.  Check date values in: |accessdate= (help)
  2. ^ Anne M. Larson, Diagnosis and management of acute liver failure, Curr Opin Gastroenterol., 2010, 26(3):212:221, 2010
  3. ^ Adams RD, Foley JM. The neurological changes in the more common types of severe liver disease. Trans American Neurology Association 1949; 74: 217-219.

External links[edit]