What is asterixis?

What is asterixis?

• A. Flapping tremors of the hands
• B. Resting tremor
• C. Muscle spasm
• D. Nystagmus

Answer: (A)

Asterixis is a motor sign characterized by a brief, nonrhythmic lapse in postural control that produces a flapping motion of the hands when the wrists are flexed. It’s often called a liver flap because it signals metabolic encephalopathy, most commonly hepatic encephalopathy from liver failure. To test for it, the arms are held with wrists dorsiflexed; the hands then show rapid, irregular flexion–extension movements—the classic flapping tremor. This differentiates it from a resting tremor (which occurs at rest, as seen in Parkinson disease), a muscle spasm (sustained contraction), or nystagmus (involuntary eye movements).

Asterixis is a motor sign characterized by a brief, nonrhythmic lapse in postural control that produces a flapping motion of the hands when the wrists are flexed. It’s often called a liver flap because it signals metabolic encephalopathy, most commonly hepatic encephalopathy from liver failure. To test for it, the arms are held with wrists dorsiflexed; the hands then show rapid, irregular flexion–extension movements—the classic flapping tremor. This differentiates it from a resting tremor (which occurs at rest, as seen in Parkinson disease), a muscle spasm (sustained contraction), or nystagmus (involuntary eye movements).