Case Report

The Stroke that Struck Back: An Unusual Alien
Hand Presentation
Andrew R. Spector, MD, William D. Freeman, MD, and William P. Cheshire, MD

Alien hand syndrome is a rare condition that can result from neurodegenerative disorders, tumors, or strokes. We encountered an acute presentation of alien hand syndrome from a right parietal ischemic stroke. The condition was not recognized by
the emergency department, delaying diagnosis and appropriate treatment. Early
recognition of unusual manifestations of stroke, such as an acute alien hand syndrome, can lead to timely diagnosis and therapy. Key Words: Alien hand
syndrome—parietal lobe—brain infarction—anterior circulation—somatosensory
cortex.
Ó 2009 by National Stroke Association

A 78-year-old woman with atrial fibrillation (not anticoagulated) was startled when her left hand suddenly
started groping about her face and striking her cheek.
After 2 hours, she presented for medical attention. The
emergency physician was suspicious for a psychiatric
movement disorder. Because the patient was not identified as having ‘‘negative’’ symptoms such as weakness,
and her initial CT head and CT angiogram were not
consistent with a major intracranial artery occlusion
(Figure 1), the emergency department stroke protocol
was not activated.
Examination by the neurology resident revealed a loss
of light touch, pinprick, proprioception, and nailbed pressure sensation in the left upper extremity. The left hand
explored the patient’s face and surrounding objects involuntarily, requiring placement of restraints. Her National
Institutes of Health Stroke Scale score was 4 (neglect,

From the Department of Neurology, Mayo Clinic, Jacksonville,
Florida.
Received June 18, 2008; revision received July 17, 2008; accepted
August 6, 2008.
Address correspondence to Andrew Spector, MD, Department of
Neurology, Mayo Clinic, 4500 San Pablo Rd, Jacksonville, FL 32224.
E-mail: Spector.andrew@mayo.edu.
1052-3057/$—see front matter
Ó 2009 by National Stroke Association
doi:10.1016/j.jstrokecerebrovasdis.2008.08.003

72

ataxia, and sensory loss of the left arm). She was given
the diagnosis of acute alien hand syndrome. Magnetic
resonance imaging confirmed a right parietal lobe infarct
(Fig 1). Magnetic resonance angiography demonstrated
a distal M2 segment occlusion of corresponding right
middle cerebral artery territory. One month later, her alien
hand resolved; she demonstrated finger pseudoathetosis
with moderate impairment of proprioception and graphesthesia.
Alien hand syndrome is a rare, distressing condition
defined as involuntary, uncontrolled, but partly purposeful movements of an arm or hand with a perception of
foreignness of the affected limb.1,2 The alien hand seems
to act on its own volition and may grope, touch, or even
strike the face or hinder purposeful actions of the other
arm. This patient’s stroke occurred during a meal, and
the alien hand prevented her dominant hand from bringing food to her mouth.
The causes of alien hand syndrome include stroke,1,3
midline tumors,1 and neurodegenerative disorders (e.g.
corticobasal degeneration, progressive supranuclear
palsy).4 Lesions frequently involve the corpus callosum
or medial frontal lobe.5 In rare instances, isolated parietal
lobe and thalamic infarcts have caused alien hand syndrome.1,3,6 The primary difference between our patient
and those with callosal or frontal causes is our patient’s
severe sensory deficit,5 which has also been seen in thalamic alien hand syndrome.7 The behavior of the alien

Journal of Stroke and Cerebrovascular Diseases, Vol. 18, No. 1 (January-February), 2009: pp 72-73

print & web 4C/FPO

AN UNUSUAL ALIEN HAND PRESENTATION

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Figure 1. (A) Noncontrast head computed tomography (CT) showing patient’s head slightly turned
with no acute changes. (B) CT perfusion blood volume showing subtle region of restricted blood volume of right temporal lobe. CT perfusion blood
volume and time to peak acquisition images are focused around M1 segments. Therefore, region of patient’s stroke was more cephalad to these perfusion
images and seen on magnetic resonance imaging
(C and D). Temporal lobe findings may have reflected temporal M2-3 branches going to parietal
stroke. (C) Diffusion-weighted image (DWI) showing moderate-sized region of restricted diffusion in
right parietal lobe in immediate postcentral location.
(D) Apparent diffusion coefficient showing restriction in corresponding region on DWI, consistent
with ischemia.

hand itself was indistinguishable from cases described in
the literature from lesions at other sites.1,5
This patient’s unusual clinical presentation and preserved strength delayed the diagnosis of stroke. As a result, we were unable to administer thrombolytic therapy.
It is important to recognize atypical presentations of acute
cerebral ischemia such as alien hand syndrome, because
misdiagnosis can delay or prevent appropriate treatment.

References
1. Kikkert MA, Ribbers GM, Koudstaal PJ. Alien hand
syndrome in stroke: A report of 2 cases and review
of the literature. Arch Phys Med Rehabil 2006;87:
728-732.

2. Assal F, Schwartz S, Vuilleumier P. Moving with or without will: Functional neural correlates of alien hand syndrome. Ann Neurol 2007;62:301-306.
3. Martı́-Fàbregas J, Kulisevsky J, Baró E, et al. Alien hand
sign after a right parietal infarction. Cerebrovasc Dis
2000;10(1):70-72.
4. Litvan I, Bhatia KP, Burn DJ, et al. SIC task force appraisal
of clinical diagnostic criteria for parkinsonian disorders.
Mov Disord 2003;18(5):467-486.
5. Brainin M, Seiser A, Matz K. The mirror world of motor inhibition: The alien hand. J Neurol Neurosurg Psychiatry
2008;79:246-252.
6. Rohde S, Weidauer S, Lanfermann H, et al. Posterior alien
hand syndrome: Case report. Neuroradiology 2002;
44:921-923.
7. Marey-Lopez J, Rubio-Nazabal E, Alonso-Magdalena L,
et al. Posterior alien hand syndrome after a right thalamic
infarct. J Neurol Neurosurg Psychiatry 2002;73:447-449.