Alien Hand Syndrome

  

Alien Hand Syndrome 

 ALIEN HAND SYNDROME by Physio Fusion

SYNONYMS
Alien limb phenomenon; Anarchic hand; Diagnostic dyspraxia; Groping-grasping
reaction; Intermanual conflict; Magnetic apraxia; Strangelovian hand; Unilateral
apraxia; Wayward hand


INTRODUCTION

Alien hand syndrome (AHS) is a higher-order motor control disorder in which a person loses control of his or her hand featuring involuntary movement but yet a purposeful movement.
It is also known as Dr. Strangelove syndrome is an interesting situation in which a person loses control of his or her hand, and the person starts to act independently.
It can affect both the side of the limb but in most cases, it usually affects the left side of the hand because the left hand is nondominant limb in about 10% of the world population.

By definition, the limb movements are not the result of movement disorders. The syndrome has been reported after surgery on the corpus callosum. They may be associated with other neurological deficits, including decreased motor spontaneity, speech hesitation, apraxia, tactile dysnomia, and behaviors associated with frontal lobe dysfunction.

MRI has been used to check the activity of the brain in the patient presented with an alien hand syndrome and also on the normal individual.
In the normal individual, it is seen that activation of multiple extensive neural networks shows after the initiation of the motor activity.
In patients with alien hand syndrome, only isolated activation of the contralateral primary motor cortex is observed. it has been suggested that it could be due to the lesions in the parietal cortex which is resulting in isolated activation of the contralateral primary motor area it might be due to the release from the intentional planning system.  There are a few causes that are known to cause this syndrome.

Common causes include
 anterior cerebral artery strokes, midline tumors, and neurodegenerative illnesses.

Rarer causes include
 spontaneous pneumocephalus, migraine aura, seizure, and Parry–Romberg Syndrome, a presumed autoimmune disorder with progressive facial hemiatrophy.

HISTORY AND NOMENCLATURE 

Alien hand syndrome is not consistently or precisely defined. It describes complex, goal-directed activity in one hand that is not voluntarily initiated. two kinds of behavior are covered by this syndrome :

First - repetitive involuntary grasping
In 1900, Liepmann drew attention to the unilateral, disinhibited grasp reflex to tactile stimulation after cerebral injury, although this phenomenon had been already proposed by  Kaiser in early 1897 
Lipmann's detailed analysis of disinhibited grasp reflex and unilateral apraxia inspired german investigators to contribute their own observation about complex movement disorder. Then Van Vleuten came and he reported a patient with a left hemisphere brain tumor that had invaded the corpus callosum. The patient grasps the object repeatedly and put down that object with his right hand. In 1908, Goldstein was the first person who indicated the "alien" quality of unilateral repetitive grasping, the impression that an alternate entity is responsible for the behavior. His patient complained was, "There must be an evil spirit in the hand!". In subsequent years this type of behavior has labeled the term, "pseudospontaneous movements" (Wilson
and Walshe 1914) "magnetic apraxia" (Denny-Brown 1958), “manual grasping behavior” (Lhermitte 1983), the"groping-grasping reaction" (Magnani et al 1987) and “visual groping” (Yagiuchi et al 1987).

Second - unilateral goal-directed limb movements that are contrary to the individual's

intention and not accounted for by repetitious grasping or unilateral apraxia.

 Van Vleuten's patient appears to have been the earliest reported instance of this condition (Van Vleuten 1907). In this case, the patient's left hand was not only apraxic, but also performed markedly incorrect actions, such as touching his right hand instead of his nose, despite his understanding of the command, and failing to move when commanded. Self-oppositional behavior, wherein one limb counteracts the declared or consciously intended action of the other limb, was often noted after the complete or partial surgical division of the corpus callosum (callosotomy) to treat refractory epilepsy.

Brion and Jedynak coined the term "the foreign hand" to describe different behaviors in patients with callosal tumors that included either the failure to recognize self-ownership of the limb or the absence of self-control over the limb's goal-directed actions.

CLINICAL MANIFESTATIONS

Alien hand syndrome is an involuntary movement disorder. The patient must be aware of the disturbance to indicate the lack of voluntary initiation of the abnormal activity. The movement must be directed to a particular object or to conduct a specific task. Nonspecific involuntary muscular contractions (eg, clonus, tremor) are excluded.

 The patient's comments may reflect depersonalization so that the affected hand assumes a distinctly different "personality." The patient may complain of the hand, "It doesn't want to stop," or, "I can't make it listen to me." 

Three kinds of the alien hand are now recognized:

1. “The frontal variant” 

The patient has disinhibited groping, an unintended reaching toward visible objects that fall within arm's reach (visual grasp) or that have been removed from contact with the hand. Self-directed grasping may also occur, which may even awaken the person from sleep (Banks et al 1989; Nicholas et al 1998; Ortega-Albas et al 2003; Giovannetti et al 2005). Once seized, the patient

has difficulty letting go of the object.

2. “The callosal variant,”

The patient's hand counteracts voluntary actions performed by the other "good" hand. For

example, the patient may pull off a sock immediately after it has been put on,

close a drawer that has just been opened, turn a car's steering wheel in the opposite direction of that of the good hand.

3. “The sensory alien hand variant” 

Ataxic limb movements associated with anesthesia or hypesthesia of the limb. The limb anesthesia prevents proprioception of limb position, and this may impair motor control of the limb as well as hinder recognizing the limb as part of one's own body.

CASE STUDY 

 

A 71-year-old right-handed woman developed acute left hemiparesis and visual hallucinations. She also complained that her left hand uncontrollably scratched her and pulled at her hair.

 Past medical history was chronic hypertension and triple coronary artery bypass graft 6 years earlier.

 Two weeks before the illness, she had felt diffusely weak; another hospital had attributed this weakness to metoprolol toxicity. When her complaints did not subside after 2 days off medication, her husband brought her to the emergency room.

 Evaluationdisclosed full orientation left lower facial weakness, right gaze bias, left hemibody

hypesthesia, and extensor posturing of the left limbs, with the left hand, constantly clenched.

 Cranial CT scan indicated acute right parietal cortical infarct and extensive bilateral subcortical white matter ischemic changes.

Cerebral MRI scan 6 days after admission confirmed the subacute right parietal infarct and diffuse bilateral subcortical ischemic changes.

 she was transferred to a rehabilitation hospital 9 days after admission. On the patient's arrival, the physician wrote in her chart, "The patient refused to attempt to do anything with that hand because 'it will hit me in the face.' The patient talks of her hand as if it were a separate entity." 

 Informal follow-up evaluation in the patient's home about 10 weeks after illness onset disclosed consistent involuntary left-hand grasp to gentle tactile stimulation and a tendency for the left hand to repeatedly touch her face with her eyes closed, despite being instructed to keep the upper extremities

extended. She also showed bilateral tactile anomia, agraphesthesia, and impaired joint position sense. Light touch sensitivity was symmetrically present in the upper extremities. The left-arm showed tonic posturing; it would either be maintained at rest with the elbow flexed or was pronated when the arms were outstretched. The right arm moved normally. No autonomous groping was observed. Further information on the patient's outpatient course is not available; she died within the year. 

Discussion

 The alien hand was suggested by the patient's involuntary self-grabbing and her referring to her hand in depersonalized terms. The etiology was somewhat unusual because the apparently acute radiologic finding was a contralateral parietal infarct. However, the neuroimaging studies suggested chronic paracallosal ischemic leukoencephalopathy. Possibly the combination of left hypesthesia induced by the acute parietal infarct with chronic medial frontal ischemia sufficed to induce alien hand. Thus, the patient showed poor awareness for the spatial location of the arm, and this, in turn, may have impaired somatosensory feedback that would otherwise have prevented her left upper extremity from groping at her face due to medial frontal injury. The medial ischemic damage alone may have been insufficient to cause an alien hand. Thus, the patient may have had the sensory alien hand variant (Ay et al 1998). Unfortunately, other case reports with similar clinical and radiologic presentations have not appeared for comparison.

DIFFERENTIAL DIAGNOSIS 

The disinhibited grasp reflex is often seen in alien hand syndrome, but it is also a common feature of either focal cerebral injury.

The grasp reflex by itself (ie, without groping or self-opposition) should not be considered alien hand, because the disturbance is comparatively simple and is less likely to disrupt patient activities. 

Unilateral spontaneous arm levitation is often an aspect of alien hand that is seen in cortical-basal ganglionic degeneration.

 unilateral spontaneous arm levitation may also appear in progressive supranuclear palsy; therefore, distinguishing between these illnesses may be difficult.

PROGNOSIS AND COMPLICATION 

When an alien hand originates from the focal injury of acute onset, recovery generally occurs within a year.  one exception case was there of alien hand that occurred following a cerebral gunshot wound to the callosum persisted for 12 years until the patient died of nonneurologic disease (Banks et al 1989). Risks of great injury to the patient that must be avoided for eg. Compulsive grasping has

also been associated with self-directed skin abrasion.

MANAGEMENT 

There is no such specific treatment has invented for this disease. One patient's alien hand interfered so much with daily activities "that his left hand had to be secured to the bed".

In the case of a frontal variant of alien hand, an oven mitt applied to the affected hand to control the compulsive movements.

 Modifications in the patient's surroundings can help to reduce fatigue and nearby distractors potentially could help to control the behavior. These approaches cannot be considered therapeutic but may be necessary to prevent injury.