Hip flexion-abduction to elicit asterixis in unresponsive patients.

Asterixis at the hip joints can be elicited by a simple diagnostic maneuver in which the hips are passively flexed and abducted about 60 to 90 degrees between the thighs. The test evoked asterixis in 8 of 10 patients who were stuporous or semicomatose because of hepatic encephalopathy. The asterixis seems to be provoked by the involuntary contraction of hip adductors against gravity.