Alien hand syndrome is a rare, neurological disorder in which the patient is unable to control either of his or her hands at will for a period of time. In most cases, damage to the cerebral bar is responsible for this phenomenon, as can result from tumorous changes, strokes, or infections.
What is alien hand syndrome?
Alien hand syndrome is a rare, neurological disorder in which the patient cannot control either of his or her hands at will for a period of time. Neurologists refer to alien hand syndrome as an extremely rare disorder in which one of the patient’s two hands escapes voluntary control and works in part against the other hand. At the beginning of the 20th century, the disorder was first documented by Kurt Goldsteins. However, the current term is not coined until a 1972 paper documenting three tumor patients with a growth on the brain bar, or corpus callosum. At that time, all three of these patients suffered from the phenomenon, which in this case was due to an interruption of the corpus callosum. Such an interruption of the corpus callosum is still considered the main scenario for the alien hand syndrome. However, in addition to the tumorous changes documented at that time, strokes, infections, or traumatic injuries to the cerebral peduncle can probably also cause the syndrome.
Causes
Due to its rarity, the causes of alien hand syndrome have been poorly understood to date. Thus, information is only available on the possible localization of brain damage that may cause the clinical picture to develop. Medical experts assume that two different scenarios can be distinguished in this respect:
If the corpus callosum is damaged, for example, the syndrome can presumably occur as well as if the frontal lobe is damaged. When the corpus callosum is damaged, communication between the two hemispheres of the brain is disrupted. Each brain hemisphere controls the opposite side of the body, and there is also an exchange of information between the left and right sides of the brain via the corpus callosum, which enables logical-analytical thought processes and makes fine-motor complex movements controllable. Thus, if the corpus callosum is damaged, coordination is also impaired – in this case preferably that of the left hand. In contrast, if the frontal lobe is causally damaged, the general planning and execution of voluntary movements is disturbed, which usually affects the dominant hand in each case.
Symptoms, complaints, and signs
In alien hand syndrome, the patient can no longer control the movements of a particular hand. It is especially common for one of the hands to work against the other, meaning that when one hand wants to write, the other gets in the way. If damage to the corpus callosum is the cause of the phenomenon, the left hand moves involuntarily, especially when the right hand is performing a movement. When the right hand is at rest, on the other hand, it remains relatively still. If the frontal lobe is damaged instead of the corpus callosum, the dominant hand is usually affected by the loss of control, in which case the syndrome often manifests itself in involuntary reaching movements for objects within its own visual field. In extreme cases, the alien hand attempts to strangle the patient against his or her will or otherwise inflicts harm.
Diagnosis and course
Because alien hand syndrome presents with a very typical and specific clinical picture, the neurologist may make the diagnosis based on mere patient observation without initiating further diagnostic procedures. He may additionally investigate the specific cause by obtaining an MRI of the brain and using imaging to learn the area of damage. As far as possible, the physician will also investigate differential diagnoses to determine whether a stroke, a tumor or an infection are associated with the phenomenon. Tumorous changes already show up in the imaging. A stroke also shows a relatively typical image on imaging, although additional examination of the brain-supplying veins may be indicated. Causative infections, on the other hand, can be diagnosed by serum, possibly CSF diagnostics, and nerve potential measurements, where they show up as delayed transmission.The course of the disease of the alien hand syndrome depends strongly on the respective cause of the disorder. However, the syndrome itself regresses after a certain time in most cases.
Complications
Alien hand syndrome, which occurs very rarely, is a possible sequela of severe brain disease or injury. Therefore, alien hand syndrome is in itself a complication of such diseases. The causes of both forms of the alien hand syndrome have not yet been sufficiently clarified. Therefore, helpful treatment approaches are also scarce so far. The only consolation for those affected is that the alien hand syndrome can regress on its own after a few years. If injuries occur due to the lack of control of a hand, complications can arise as a result of the impaired perception of the hand. Lack of wound care on the hand, which is perceived as a foreign body, can have consequences that require treatment. In addition, psychological problems can occur as a result of these rare conditions. When a hand does things that are beyond one’s control of will, this can be emotionally very stressful. Since there is hardly any treatment strategy so far, the affected persons are very limited in their lives. In most cases, they can no longer practice their profession. They often withdraw from public life. Many immobilize the affected arm. As often falsely portrayed in movies, alien hand syndrome can lead to a desire for amputation in the affected person due to the hand acting on its own. However, this is nonsensical from a medical point of view. It makes much more sense to improve this condition by daily training of the affected hand.
When should you go to the doctor?
As a rule, alien hand syndrome is not a disease in its own right, so targeted and causal treatment is usually not possible. However, alien hand syndrome can give many indications of certain diseases and should therefore be examined by a doctor in any case. As a rule, the alien hand syndrome occurs after a stroke or after injuries to the head or directly to the brain. If such injuries have occurred before, this syndrome can be treated and limited in some cases. However, a positive course of the disease cannot be predicted in general. Furthermore, the syndrome may indicate a tumor, which may still be removed if diagnosed in time. If the causal treatment of this disease is successful, the symptoms of the alien hand syndrome usually disappear after a short time and do not lead to further complications. The disease can be diagnosed by a general practitioner. However, further treatment depends on the cause and is therefore performed at a specialist.
Treatment and therapy
Alien hand syndrome itself can be treated only provisionally, such as by immobilizing the affected hand to prevent it from involuntary movement. Rarely, physiotherapeutic training produces an educational effect of the hand, which weakens the syndrome or makes it disappear completely. However, since the phenomenon usually recedes after a certain time anyway, the focus of treatment is primarily on bringing the affected person’s quality of life back closer to the norm for the period of the disorder. Depending on which disease has caused the symptom, the causative disease must also be treated. If tumorous changes in the frontal lobe or the corpus callosum are evident, the physician will initiate surgical removal as far as possible. On the other hand, if a stroke has been shown to be causative, conventional stroke prevention can be initiated. In turn, if the brain is infected, such as by bacteria, patients are usually treated in intensive care, with drug treatment and fluid administration being as significant as fever-reducing measures.
Outlook and prognosis
Alien hand syndrome usually causes various symptoms and complications in the patient. In most cases, regions of the brain may become so damaged that paralysis or other disturbances of sensitivity occur. Similarly, motor impairments may also occur. Movement of the hands and feet may also be limited by alien hand syndrome. In severe cases, the affected person’s hand may also attempt to harm the patient itself.Furthermore, the alien hand syndrome leads to extreme depression and other psychological complaints. The quality of life is significantly reduced and limited by this disease. Often the patients are also dependent on the help of other people in their everyday life. Alien hand syndrome can be treated with the help of various therapies. However, in some cases there is also spontaneous improvement. Unfortunately, in general, no prognosis can be given. Often, however, the symptoms can be alleviated by therapies, so that the affected person can use his hands normally again. Life expectancy is not limited by alien hand syndrome.
Prevention
Alien hand syndrome cannot be prevented. However, because it is an extremely rare condition, no one should live in fear of the syndrome anyway.
Follow-up
The need for follow-up care in alien hand syndrome first addresses the underlying triggering problem. Therefore, medical follow-up initially focuses on managing the neurological causes of alien hand syndrome, namely tumors, strokes, and similarly severe neurological conditions. Whether these neurological disorders can be treated surgically or with medication varies. However, since the causative agents of the alien hand syndrome cannot always be detected, follow-up is standardized only for recognized causative agents. In case of undetectable causes, it becomes difficult with the follow-up. The only thing that is clear is that the cause of the phenomenon is a brain-related disorder or neurological disease in the brain. Follow-up care for alien hand syndrome is difficult if only because there are hardly any treatment approaches for the syndrome itself so far. Only the underlying disease can be medically treated. The only consolation for those affected is that with the treatment and improvement of the causative symptoms, the alien hand syndrome often improves as well. It can disappear on its own if the triggering underlying disease has been successfully treated. As a measure of aftercare for the affected hand, targeted training of the uncontrolled hand has proven helpful. Nevertheless, the affected persons are often severely restricted in their future life. They usually require home-based assistance and should receive regular medical follow-up.
Here’s what you can do yourself
Along with the fact that there is no known treatment for alien hand syndrome, the options available to sufferers to alleviate their symptoms are also quickly exhausted. A few methods can be applied, whereby the successes are very individual and therefore no promise of improvement can be given. It has only been shown that continuous occupation of the affected hand can make it calmer. For example, it can be entrusted with everyday objects, which should be designed so that they can be easily grasped and felt. Small, soft balls and pens are often used. For sufferers who are disturbed by their hand while sleeping, a potty mitt before bedtime may help. Decreasing the sensory sensitivity of the Alien Hand may limit its activity. Constant repetition of tasks that involve both hands can also teach the affected hand certain movement patterns. Which exercises these are and how complex they may be, however, must be determined individually and are not always associated with success. The most important thing here is simplicity. Affected persons can study the behavior of their malfunctioning hand in order to recognize possible patterns in the arbitrary actions of the hand. In some cases, this can prevent interference from the Alien Hand by adjusting movement patterns.
