Case Report: 84 year-old woman with alien hand syndrome.

Background: Alien hand syndrome [AHS] is a rare and ill-defined neurological disorder. It produces complex, goal-directed motion of one hand that is involuntarily instigated. This syndrome characteristically arises after brain trauma, brain surgery, stroke or encephalitis. We describe a case of AHS in a patient who had a previous episode of subarachnoid hemorrhage affecting the left frontal lobe and corpus callosum. Case presentation: An 84-year-old woman presented to the emergency department complaining of headaches and several episodes of her left arm moving as if it was groping around trying to grab at her own body. A computed tomography scan of the head demonstrated an acute left superior frontal hemorrhage with compression of the corpus callosum. Transcranial Doppler report showed no significant abnormality in the insonated vessels. After being stabilized for the acute bleed, she was treated with clonazepam 0.5 mgat night for the uncontrolled hand movements. Her movements resolved by her next month follow up. The diagnosis of AHS was made based on her clinical presentation, characterization of the movement and localization correlating with findings in neuroimaging. Conclusion: We document a rare neurologic disorder seen in patients presenting with a history of previous strokes and a typical description of involuntary and unintentional, uncontrolled unilateral arm movements with repetitive grasping. The present case has a combination of frontal and callosal lesions.  These findings appear to support a potential destruction leading to the rare syndrome.