Dystonia
Encyclopedia
Dystonia is a neurological
movement disorder
, in which sustained muscle contractions cause twisting and repetitive movements or abnormal postures. The disorder may be hereditary or caused by other factors such as birth-related
or other physical trauma
, infection
, poisoning (e.g., lead poisoning
) or reaction to pharmaceutical drugs, particularly neuroleptics. Treatment is difficult and has been limited to minimizing the symptoms of the disorder, since there is no cure available.
The combination of blepharospasmodic contractions and oromandibular dystonia
is called cranial dystonia or Meige's syndrome
.
There is a group called myoclonus dystonia or myoclonic dystonia
, where some cases are hereditary and have been associated with a missense mutation
in the dopamine-D2 receptor
. Some of these cases have responded remarkably to alcohol.
Early symptoms may include loss of precision muscle coordination (sometimes first manifested in declining penmanship, frequent small injuries to the hands, and dropped items), cramping pain with sustained use and trembling. Significant muscle pain and cramping may result from very minor exertions like holding a book and turning pages. It may become difficult to find a comfortable position for arms and legs with even the minor exertions associated with holding arms crossed causing significant pain similar to restless leg syndrome. Affected persons may notice trembling in the diaphragm
while breathing, or the need to place hands in pockets, under legs while sitting or under pillows while sleeping to keep them still and to reduce pain. Trembling in the jaw may be felt and heard while lying down, and the constant movement to avoid pain may result in the grinding and wearing down of teeth, or symptoms similar to TMD
. The voice may crack frequently or become harsh, triggering frequent throat clearing. Swallowing can become difficult and accompanied by painful cramping.
Electrical sensors (EMG) inserted into affected muscle groups, while painful, can provide a definitive diagnosis by showing pulsating nerve signals being transmitted to the muscles even when they are at rest. The brain appears to signal portions of fibers within the affected muscle groups at a firing speed of about 10 Hz causing them to pulsate, tremble and contort. When called upon to perform an intentional activity, the muscles fatigue very quickly and some portions of the muscle groups do not respond (causing weakness) while other portions over-respond or become rigid (causing micro-tears under load). The symptoms worsen significantly with use, especially in the case of focal dystonia, and a "mirror effect" is often observed in other body parts: use of the right hand may cause pain and cramping in that hand as well as in the other hand and legs that were not being used. Stress, anxiety, lack of sleep, sustained use and cold temperatures can worsen symptoms.
Direct symptoms may be accompanied by secondary effects of the continuous muscle and brain activity, including disturbed sleep patterns, exhaustion, mood swings, mental stress, difficulty concentrating, blurred vision, digestive problems and short temper. People with dystonia may also become depressed and find great difficulty adapting their activities and livelihood to a progressing disability. Side effects from treatment and medications can also present challenges in normal activities.
In some cases, symptoms may progress and then plateau for years, or stop progressing entirely. The progression may be delayed by treatment or adaptive lifestyle changes, while forced continued use may make symptoms progress more rapidly. In others, the symptoms may progress to total disability, making some of the more risky forms of treatment worth considering. In some cases with patients who already have dystonia, a subsequent tramatic injury or the effects of general anethesia during an unrelated surgery can cause the symptoms to progress rapidly.
An accurate diagnosis may be difficult because of the way the disorder manifests itself. Sufferers may be diagnosed as having similar and perhaps related disorders including Parkinson's disease
, essential tremor
, carpal tunnel syndrome
, TMD
, Tourette's syndrome, or other neuromuscular movement disorders. It has been found that the prevalence of dystonia is high in individuals with Huntington’s disease, where the most common clinical presentations are internal shoulder rotation, sustained fist clenching, knee flexion, and foot inversion. Risk factors for increased dystonia in patients with Huntington’s disease include long disease duration and use of antidopaminergic medication.
Primary dystonia is suspected to be caused by a pathology of the central nervous system
, likely originating in those parts of the brain
concerned with motor function, such as the basal ganglia
, and the GABA (gamma-aminobutyric acid
) producing Purkinje neurons. The precise cause of primary dystonia is unknown. In many cases it may involve some genetic predisposition towards the disorder combined with environmental conditions.
Secondary dystonia refers to dystonia brought on by some identified cause, usually involving brain damage, or by some unidentified cause such as chemical imbalance. Some cases of (particularly focal) dystonia are brought on after trauma, are induced by certain drugs (tardive dystonia
), or may be the result of diseases of the nervous system such as Wilson's disease
.
Environmental and task-related factors are suspected to trigger the development of focal dystonias because they appear disproportionately in individuals who perform high precision hand movements such as musicians, engineers, architects and artists. Chlorpromazine can also cause dystonia, which can be often misjudged as a seizure.
Neuroleptic drugs often cause dystonia, including oculogyric crisis.
or occupational therapy
can directly treat dystonia, they can be utilized to manage changes in balance, mobility and overall function that occur as a result of the disorder. A variety of treatment strategies can be employed to address the unique needs of each individual. Potential treatment interventions include splinting, therapeutic exercise, manual stretching
, soft tissue and joint mobilization
, postural training, neuromuscular electrical stimulation, constraint-induced movement therapy
, activity and environmental modification, and gait training
. Due to the rare and variable nature of dystonia, research investigating the effectiveness of these treatments is limited. To date, focal cervical dystonia has received the most research attention; however, study designs are poorly controlled and limited to small sample sizes.
Some focal dystonias have been proven treatable through movement retraining in the Taubman approach, particularly in the case of musicians. However other focal dystonias may not respond and may even be made worse by this treatment.
, benzatropine, anti-Parkinsons agents ( such as trihexyphenidyl
), and muscle relaxers (such as diazepam
).
Cannabidiol
, one of the non-psychoactive cannabinoids found in cannabis sativa
, was shown in a 6-week study to have reduced dystonic symptoms in all participants by up to 20-50%.
Anticholinergics
Medications such as anticholinergic
s (benztropine), which act as inhibitors of the neurotransmitter acetylcholine
, may provide some relief. In the case of an acute dystonic reaction, diphenhydramine
is sometimes used (though this drug is well known as an antihistamine
, in this context it is being used primarily for its anticholinergic role). In the case of Oculogyric crisis, diphenhydramine
may be administered with excellent results with symptoms subsiding in a matter of minutes.
Muscle relaxants
Clonazepam
, an anti-seizure medicine, is also sometimes prescribed. However, for most their effects are limited and side effects like mental confusion, sedation, mood swings and short-term memory loss occur.
Botulinum toxin
injections into affected muscles have proved quite successful in providing some relief for around 3–6 months, depending on the kind of dystonia. Botox injections have the advantage of ready availability (the same form is used for cosmetic surgery) and the effects are not permanent. There is a risk of temporary paralysis of the muscles being injected or the leaking of the toxin into adjacent muscle groups causing weakness or paralysis in them. The injections have to be repeated as the effects wear off and around 15% of recipients will develop immunity to the toxin. There is a Type A and Type B toxin approved for treatment of dystonia; often those that develop resistance to Type A may be able to use Type B.
Noting that botulinum toxin has been shown to have an effect on inhibiting neurogenic inflammation, and evidence suggesting the role of neurogenic inflammation in the pathogenesis of psoriasis, the University of Minnesota has begun a clinical trial to follow up on the observation that patients treated with botulinum toxin for dystonia had dramatic improvement in psoriasis. See: Use of Botulinum Toxin to Treat Psoriasis.
Parkinsonian drugs
Dopamine agonist
s: One type of dystonia, dopamine-responsive dystonia
, can be completely treated with regular doses of L-DOPA in a form such as Sinemet (carbidopa/levodopa). Although this doesn't remove the condition, it does alleviate the symptoms most of the time. (In contrast, dopamine antagonist
s can sometimes cause dystonia.)
Baclofen
A baclofen
pump has been used to treat patients of all ages exhibiting muscle spasticity along with dystonia. The pump delivers baclofen via a catheter to the thecal space surrounding the spinal cord. The pump itself is placed in the abdomen. It can be refilled periodically by access through the skin.
(DBS) has proven successful in a number of cases of severe generalised dystonia. DBS as treatment for medication-refractory dystonia, on the other hand, may increase the risk of suicide in patients. Unfortunately, reference data of patients without DBS therapy are lacking.
Neurology
Neurology is a medical specialty dealing with disorders of the nervous system. Specifically, it deals with the diagnosis and treatment of all categories of disease involving the central, peripheral, and autonomic nervous systems, including their coverings, blood vessels, and all effector tissue,...
movement disorder
Movement disorder
Movement disorders include:* Akathisia * Akinesia * Associated Movements * Athetosis...
, in which sustained muscle contractions cause twisting and repetitive movements or abnormal postures. The disorder may be hereditary or caused by other factors such as birth-related
Birth trauma (physical)
Birth trauma is damage to the tissues and organs of an infant caused by mechanical forces during childbirth often accompanied by impaired blood circulation and organ functioning...
or other physical trauma
Physical trauma
Trauma refers to "a body wound or shock produced by sudden physical injury, as from violence or accident." It can also be described as "a physical wound or injury, such as a fracture or blow." Major trauma can result in secondary complications such as circulatory shock, respiratory failure and death...
, infection
Infection
An infection is the colonization of a host organism by parasite species. Infecting parasites seek to use the host's resources to reproduce, often resulting in disease...
, poisoning (e.g., lead poisoning
Lead poisoning
Lead poisoning is a medical condition caused by increased levels of the heavy metal lead in the body. Lead interferes with a variety of body processes and is toxic to many organs and tissues including the heart, bones, intestines, kidneys, and reproductive and nervous systems...
) or reaction to pharmaceutical drugs, particularly neuroleptics. Treatment is difficult and has been limited to minimizing the symptoms of the disorder, since there is no cure available.
Types of dystonia
- Generalized
- Focal
- Segmental
- Sexual
- Intermediate
- Acute Dystonic Reaction
Generalized dystonias
- Normal birth history and milestones
- Autosomal dominant
- Childhood onset
- Starts in lower limbs and spreads upwards
- Also known as "idiopathic torsion dystonia" (old terminology "dystonia musculorum deformans")
Focal dystonias
These are the most common dystonias and tend to be classified as follows:| Name | Location | Description |
|---|---|---|
| Anismus Anismus Anismus is a malfunction of the external anal sphincter and puborectalis muscle during defecation. Normal defecation involves relaxation of both of these muscles... |
muscles of the rectum Rectum The rectum is the final straight portion of the large intestine in some mammals, and the gut in others, terminating in the anus. The human rectum is about 12 cm long... |
Causes painful defecation, constipation Constipation Constipation refers to bowel movements that are infrequent or hard to pass. Constipation is a common cause of painful defecation... ; may be complicated by encopresis Encopresis Encopresis is involuntary fecal soiling in adults and children who have usually already been toilet trained. Persons with encopresis often leak stool into their undergarments.-Prevalence:The estimated prevalence of encopresis in four-year-olds is between one and three percent... . |
| Cervical dystonia (spasmodic torticollis Spasmodic torticollis Spasmodic torticollis is a chronic neurological movement disorder causing the neck to involuntarily turn to the left, right, upwards, and/or downwards. The condition is also referred to as "cervical dystonia". Both agonist and antagonist muscle contract simultaneously during dystonic... ) |
muscles of the neck Neck The neck is the part of the body, on many terrestrial or secondarily aquatic vertebrates, that distinguishes the head from the torso or trunk. The adjective signifying "of the neck" is cervical .-Boner anatomy: The cervical spine:The cervical portion of the human spine comprises seven boney... |
Causes the head to rotate to one side, to pull down towards the chest, or back, or a combination of these postures. |
| Blepharospasm Blepharospasm A blepharospasm , is any abnormal contraction or twitch of the eyelid.... |
muscles around the eyes | The sufferer experiences rapid blinking of the eyes or even their forced closure causing effective blindness. |
| Oculogyric crisis Oculogyric crisis Oculogyric crisis is the name of a dystonic reaction to certain drugs or medical conditions. The term "Oculogyric" refers to rotating of eyeballs, but several other responses are associated with the crisis.-Causes:... |
muscles of eye and head | An extreme and sustained (usually) upward deviation of the eyes often with convergence causing diplopia Diplopia Diplopia, commonly known as double vision, is the simultaneous perception of two images of a single object that may be displaced horizontally, vertically, or diagonally in relation to each other... . It is frequently associated with backwards and lateral flexion of the neck and either widely opened mouth or jaw clenching. Frequently a result of antiemetics such as the neuroleptics (e.g., prochlorperazine Prochlorperazine Prochlorperazine is a dopamine receptor antagonist that belongs to the phenothiazine class of antipsychotic agents that are used for the antiemetic treatment of nausea and vertigo. It is also a highly-potent typical antipsychotic, 10-20x more potent than chlorpromazine... ) or metoclopramide Metoclopramide Metoclopramide is an antiemetic and gastroprokinetic agent. It is commonly used to treat nausea and vomiting, to facilitate gastric emptying in people with gastroparesis, and as a treatment for the gastric stasis often associated with migraine headaches.-Medical uses:Metoclopramide is commonly... . Also can be caused by Chlorpromazine Chlorpromazine Chlorpromazine is a typical antipsychotic... |
| Oromandibular dystonia Oromandibular dystonia Oromandibular dystonia is a form of focal dystonia affecting the mouth, jaw, and tongue.Botulinum toxin has been used in treatment.... |
muscles of the jaw and muscles of tongue Muscles of tongue The muscles of tongue can be divided into intrinsic and extrinsic groups.The intrinsic muscles lie entirely within the tongue, while the extrinsic muscles attach the tongue to other structures.... |
Causes distortions of the mouth and tongue. |
| Spasmodic dysphonia Spasmodic dysphonia Spasmodic dysphonia is a voice disorder characterized by involuntary movements of one or more muscles of the larynx during speech.- Types of spasmodic dysphonia :... /Laryngeal dystonia |
muscles of larynx Muscles of larynx The muscles of the larynx are extrinsic, passing between the larynx and parts around; and intrinsic, confined entirely to the larynx.The intrinsic muscles are divided into respiratory and the phonatory muscles . The respiratory muscles move the vocal chords apart and serve breathing... |
Causes the voice to sound broken or reducing it to a whisper. |
| Focal hand dystonia (also known as musician's or writer's cramp Writer's cramp Writer's cramp, also called mogigraphia and scrivener's palsy, causes a cramp or spasm affecting certain muscles of the hand and/or fingers. Writer's cramp is a task-specific focal dystonia of the hand... ). |
single muscle or small group of muscles in the hand | It interferes with activities such as writing or playing a musical instrument by causing involuntary muscular contractions. The condition is sometimes "task-specific," meaning that it is generally only apparent during certain activities. Focal hand dystonia is neurological in origin, and is not due to normal fatigue. The loss of precise muscle control and continuous unintentional movement results in painful cramping and abnormal positioning that makes continued use of the affected body parts impossible. |
The combination of blepharospasmodic contractions and oromandibular dystonia
Oromandibular dystonia
Oromandibular dystonia is a form of focal dystonia affecting the mouth, jaw, and tongue.Botulinum toxin has been used in treatment....
is called cranial dystonia or Meige's syndrome
Meige's syndrome
Meige's syndrome is a type of dystonia. It is also known as Brueghel's syndrome and oral facial dystonia. It is actually a combination of two forms of dystonia, blepharospasm and oromandibular dystonia ....
.
Segmental dystonias
Segmental dystonias affect two adjoining parts of the body:- Hemidystonia affects an arm and foot on one side of the body.
- Multifocal dystonia affects many different parts of the body.
- Generalized dystonia affects most of the body, frequently involving the legs and back.
Genetic / primary
There is a group called myoclonus dystonia or myoclonic dystonia
Myoclonic dystonia
Myoclonic distonia or Myoclonus-dystonia syndrome is a rare syndrome having several subforms each traced to a different gene. The uniting feature is dystonia, but there are also rapid jerky movements resembling myoclonus....
, where some cases are hereditary and have been associated with a missense mutation
Missense mutation
In genetics, a missense mutation is a point mutation in which a single nucleotide is changed, resulting in a codon that codes for a different amino acid . This can render the resulting protein nonfunctional...
in the dopamine-D2 receptor
Dopamine receptor D2
Dopamine receptor D2, also known as D2R, is a protein that, in humans, is encoded by the DRD2 gene.- Function :This gene encodes the D2 subtype of the dopamine receptor. This G protein-coupled receptor inhibits adenylyl cyclase activity...
. Some of these cases have responded remarkably to alcohol.
Signs and symptoms
Symptoms vary according to the kind of dystonia involved. In most cases, dystonia tends to lead to abnormal posturing, particularly on movement. Many sufferers have continuous pain, cramping and relentless muscle spasms due to involuntary muscle movements. Other motor symptoms are possible including lip smacking.Early symptoms may include loss of precision muscle coordination (sometimes first manifested in declining penmanship, frequent small injuries to the hands, and dropped items), cramping pain with sustained use and trembling. Significant muscle pain and cramping may result from very minor exertions like holding a book and turning pages. It may become difficult to find a comfortable position for arms and legs with even the minor exertions associated with holding arms crossed causing significant pain similar to restless leg syndrome. Affected persons may notice trembling in the diaphragm
Thoracic diaphragm
In the anatomy of mammals, the thoracic diaphragm, or simply the diaphragm , is a sheet of internal skeletal muscle that extends across the bottom of the rib cage. The diaphragm separates the thoracic cavity from the abdominal cavity and performs an important function in respiration...
while breathing, or the need to place hands in pockets, under legs while sitting or under pillows while sleeping to keep them still and to reduce pain. Trembling in the jaw may be felt and heard while lying down, and the constant movement to avoid pain may result in the grinding and wearing down of teeth, or symptoms similar to TMD
Temporomandibular joint disorder
Temporomandibular joint disorder , or TMJ syndrome, is an umbrella term covering acute or chronic inflammation of the temporomandibular joint, which connects the mandible to the skull. The disorder and resultant dysfunction can result in significant pain and impairment...
. The voice may crack frequently or become harsh, triggering frequent throat clearing. Swallowing can become difficult and accompanied by painful cramping.
Electrical sensors (EMG) inserted into affected muscle groups, while painful, can provide a definitive diagnosis by showing pulsating nerve signals being transmitted to the muscles even when they are at rest. The brain appears to signal portions of fibers within the affected muscle groups at a firing speed of about 10 Hz causing them to pulsate, tremble and contort. When called upon to perform an intentional activity, the muscles fatigue very quickly and some portions of the muscle groups do not respond (causing weakness) while other portions over-respond or become rigid (causing micro-tears under load). The symptoms worsen significantly with use, especially in the case of focal dystonia, and a "mirror effect" is often observed in other body parts: use of the right hand may cause pain and cramping in that hand as well as in the other hand and legs that were not being used. Stress, anxiety, lack of sleep, sustained use and cold temperatures can worsen symptoms.
Direct symptoms may be accompanied by secondary effects of the continuous muscle and brain activity, including disturbed sleep patterns, exhaustion, mood swings, mental stress, difficulty concentrating, blurred vision, digestive problems and short temper. People with dystonia may also become depressed and find great difficulty adapting their activities and livelihood to a progressing disability. Side effects from treatment and medications can also present challenges in normal activities.
In some cases, symptoms may progress and then plateau for years, or stop progressing entirely. The progression may be delayed by treatment or adaptive lifestyle changes, while forced continued use may make symptoms progress more rapidly. In others, the symptoms may progress to total disability, making some of the more risky forms of treatment worth considering. In some cases with patients who already have dystonia, a subsequent tramatic injury or the effects of general anethesia during an unrelated surgery can cause the symptoms to progress rapidly.
An accurate diagnosis may be difficult because of the way the disorder manifests itself. Sufferers may be diagnosed as having similar and perhaps related disorders including Parkinson's disease
Parkinson's disease
Parkinson's disease is a degenerative disorder of the central nervous system...
, essential tremor
Essential tremor
Essential tremor is a slowly progressive neurological disorder whose most recognizable feature is a tremor of the arms that is apparent during voluntary movements such as eating and writing...
, carpal tunnel syndrome
Carpal tunnel syndrome
Carpal Tunnel Syndrome is an entrapment idiopathic median neuropathy, causing paresthesia, pain, and other symptoms in the distribution of the median nerve due to its compression at the wrist in the carpal tunnel. The pathophysiology is not completely understood but can be considered compression...
, TMD
Temporomandibular joint disorder
Temporomandibular joint disorder , or TMJ syndrome, is an umbrella term covering acute or chronic inflammation of the temporomandibular joint, which connects the mandible to the skull. The disorder and resultant dysfunction can result in significant pain and impairment...
, Tourette's syndrome, or other neuromuscular movement disorders. It has been found that the prevalence of dystonia is high in individuals with Huntington’s disease, where the most common clinical presentations are internal shoulder rotation, sustained fist clenching, knee flexion, and foot inversion. Risk factors for increased dystonia in patients with Huntington’s disease include long disease duration and use of antidopaminergic medication.
Causes
The causes of dystonia are not yet known or understood; however, they are categorized as follows on a theoretical basis:Primary dystonia is suspected to be caused by a pathology of the central nervous system
Central nervous system
The central nervous system is the part of the nervous system that integrates the information that it receives from, and coordinates the activity of, all parts of the bodies of bilaterian animals—that is, all multicellular animals except sponges and radially symmetric animals such as jellyfish...
, likely originating in those parts of the brain
Brain
The brain is the center of the nervous system in all vertebrate and most invertebrate animals—only a few primitive invertebrates such as sponges, jellyfish, sea squirts and starfishes do not have one. It is located in the head, usually close to primary sensory apparatus such as vision, hearing,...
concerned with motor function, such as the basal ganglia
Basal ganglia
The basal ganglia are a group of nuclei of varied origin in the brains of vertebrates that act as a cohesive functional unit. They are situated at the base of the forebrain and are strongly connected with the cerebral cortex, thalamus and other brain areas...
, and the GABA (gamma-aminobutyric acid
Gamma-aminobutyric acid
γ-Aminobutyric acid is the chief inhibitory neurotransmitter in the mammalian central nervous system. It plays a role in regulating neuronal excitability throughout the nervous system...
) producing Purkinje neurons. The precise cause of primary dystonia is unknown. In many cases it may involve some genetic predisposition towards the disorder combined with environmental conditions.
Secondary dystonia refers to dystonia brought on by some identified cause, usually involving brain damage, or by some unidentified cause such as chemical imbalance. Some cases of (particularly focal) dystonia are brought on after trauma, are induced by certain drugs (tardive dystonia
Tardive dyskinesia
Tardive dyskinesia is a difficult-to-treat form of dyskinesia that can be tardive...
), or may be the result of diseases of the nervous system such as Wilson's disease
Wilson's disease
Wilson's disease or hepatolenticular degeneration is an autosomal recessive genetic disorder in which copper accumulates in tissues; this manifests as neurological or psychiatric symptoms and liver disease...
.
Environmental and task-related factors are suspected to trigger the development of focal dystonias because they appear disproportionately in individuals who perform high precision hand movements such as musicians, engineers, architects and artists. Chlorpromazine can also cause dystonia, which can be often misjudged as a seizure.
Neuroleptic drugs often cause dystonia, including oculogyric crisis.
Treatment
Treatment has been limited to minimizing the symptoms of the disorder as there is yet no successful treatment for its cause. Reducing the types of movements that trigger or worsen dystonic symptoms provides some relief, as does reducing stress, getting plenty of rest, moderate exercise, and relaxation techniques. Various treatments focus on sedating brain functions or blocking nerve communications with the muscles via drugs, neuro-suppression or denervation. All current treatments have negative side effects and risks.Physical intervention
Although neither physical therapyPhysical therapy
Physical therapy , often abbreviated PT, is a health care profession. Physical therapy is concerned with identifying and maximizing quality of life and movement potential within the spheres of promotion, prevention, diagnosis, treatment/intervention,and rehabilitation...
or occupational therapy
Occupational therapy
Occupational therapy is a discipline that aims to promote health by enabling people to perform meaningful and purposeful activities. Occupational therapists work with individuals who suffer from a mentally, physically, developmentally, and/or emotionally disabling condition by utilizing treatments...
can directly treat dystonia, they can be utilized to manage changes in balance, mobility and overall function that occur as a result of the disorder. A variety of treatment strategies can be employed to address the unique needs of each individual. Potential treatment interventions include splinting, therapeutic exercise, manual stretching
Stretching
Stretching is a form of physical exercise in which a specific skeletal muscle is deliberately elongated, often by abduction from the torso, in order to improve the muscle's felt elasticity and reaffirm comfortable muscle tone. The result is a feeling of increased muscle control, flexibility and...
, soft tissue and joint mobilization
Joint mobilization
Joint mobilization is a type of passive movement of a skeletal joint. It is usually aimed at a 'target' synovial joint with the aim of achieving a therapeutic effect...
, postural training, neuromuscular electrical stimulation, constraint-induced movement therapy
Constraint-induced movement therapy
Constraint-induced movement therapy is a form of rehabilitation therapy that improves upper extremity function in stroke and other Central Nervous System damage victims by increasing the use of their affected upper limb....
, activity and environmental modification, and gait training
Gait training
In its most general form, Gait training is the act of learning how to walk. However, the term is more often used in reference to a person learning how to walk again after injury or with a disability...
. Due to the rare and variable nature of dystonia, research investigating the effectiveness of these treatments is limited. To date, focal cervical dystonia has received the most research attention; however, study designs are poorly controlled and limited to small sample sizes.
Some focal dystonias have been proven treatable through movement retraining in the Taubman approach, particularly in the case of musicians. However other focal dystonias may not respond and may even be made worse by this treatment.
Medication
Different medications are tried in an effort to find a combination that is effective for a specific person. Not all people will respond well to the same medications. Medications that have had positive results in some include: diphenhydramineDiphenhydramine
Diphenhydramine hydrochloride is a first-generation antihistamine possessing anticholinergic, antitussive, antiemetic, and sedative properties which is mainly used to treat allergies. Like most other first-generation antihistamines, the drug also has a powerful hypnotic effect, and for this reason...
, benzatropine, anti-Parkinsons agents ( such as trihexyphenidyl
Trihexyphenidyl
Trihexyphenidyl , also known as benzhexol, is an antiparkinsonian agent of the antimuscarinic class. It has been in clinical usage for decades...
), and muscle relaxers (such as diazepam
Diazepam
Diazepam , first marketed as Valium by Hoffmann-La Roche is a benzodiazepine drug. Diazepam is also marketed in Australia as Antenex. It is commonly used for treating anxiety, insomnia, seizures including status epilepticus, muscle spasms , restless legs syndrome, alcohol withdrawal,...
).
Cannabidiol
Cannabidiol
Cannabidiol is a cannabinoid found in Cannabis. It is a major constituent of the plant, representing up to 40% in its extracts.It has displayed sedative effects in animal tests...
, one of the non-psychoactive cannabinoids found in cannabis sativa
Cannabis sativa
Cannabis sativa is an annual herbaceous plant in the Cannabaceae family. Humans have cultivated this herb throughout recorded history as a source of industrial fibre, seed oil, food, recreation, spiritual enlightenment and medicine...
, was shown in a 6-week study to have reduced dystonic symptoms in all participants by up to 20-50%.
Anticholinergics
Medications such as anticholinergic
Anticholinergic
An anticholinergic agent is a substance that blocks the neurotransmitter acetylcholine in the central and the peripheral nervous system. An example of an anticholinergic is dicycloverine, and the classic example is atropine....
s (benztropine), which act as inhibitors of the neurotransmitter acetylcholine
Acetylcholine
The chemical compound acetylcholine is a neurotransmitter in both the peripheral nervous system and central nervous system in many organisms including humans...
, may provide some relief. In the case of an acute dystonic reaction, diphenhydramine
Diphenhydramine
Diphenhydramine hydrochloride is a first-generation antihistamine possessing anticholinergic, antitussive, antiemetic, and sedative properties which is mainly used to treat allergies. Like most other first-generation antihistamines, the drug also has a powerful hypnotic effect, and for this reason...
is sometimes used (though this drug is well known as an antihistamine
Antihistamine
An H1 antagonist is a histamine antagonist of the H1 receptor that serves to reduce or eliminate effects mediated by histamine, an endogenous chemical mediator released during allergic reactions...
, in this context it is being used primarily for its anticholinergic role). In the case of Oculogyric crisis, diphenhydramine
Diphenhydramine
Diphenhydramine hydrochloride is a first-generation antihistamine possessing anticholinergic, antitussive, antiemetic, and sedative properties which is mainly used to treat allergies. Like most other first-generation antihistamines, the drug also has a powerful hypnotic effect, and for this reason...
may be administered with excellent results with symptoms subsiding in a matter of minutes.
Muscle relaxants
Clonazepam
Clonazepam
Clonazepamis a benzodiazepine drug having anxiolytic, anticonvulsant, muscle relaxant, and hypnotic properties. It is marketed by Roche under the trade name Klonopin in the United States and Rivotril in Australia, Brazil, Canada and Europe...
, an anti-seizure medicine, is also sometimes prescribed. However, for most their effects are limited and side effects like mental confusion, sedation, mood swings and short-term memory loss occur.
Botulinum toxin
Botulinum toxin
Botulinum toxin is a protein produced by the bacterium Clostridium botulinum, and is considered the most powerful neurotoxin ever discovered. Botulinum toxin causes Botulism poisoning, a serious and life-threatening illness in humans and animals...
injections into affected muscles have proved quite successful in providing some relief for around 3–6 months, depending on the kind of dystonia. Botox injections have the advantage of ready availability (the same form is used for cosmetic surgery) and the effects are not permanent. There is a risk of temporary paralysis of the muscles being injected or the leaking of the toxin into adjacent muscle groups causing weakness or paralysis in them. The injections have to be repeated as the effects wear off and around 15% of recipients will develop immunity to the toxin. There is a Type A and Type B toxin approved for treatment of dystonia; often those that develop resistance to Type A may be able to use Type B.
Noting that botulinum toxin has been shown to have an effect on inhibiting neurogenic inflammation, and evidence suggesting the role of neurogenic inflammation in the pathogenesis of psoriasis, the University of Minnesota has begun a clinical trial to follow up on the observation that patients treated with botulinum toxin for dystonia had dramatic improvement in psoriasis. See: Use of Botulinum Toxin to Treat Psoriasis.
Parkinsonian drugs
Dopamine agonist
Dopamine agonist
A dopamine agonist is a compound that activates dopamine receptors in the absence of dopamine. Dopamine agonists activate signaling pathways through the dopamine receptor and trimeric G-proteins, ultimately leading to changes in gene transcription.-Uses:...
s: One type of dystonia, dopamine-responsive dystonia
Dopamine-responsive dystonia
Dopamine-responsive dystonia , also known as hereditary progressive dystonia with diurnal fluctuation, Segawa's disease, or Segawa's dystonia, is a genetic movement disorder which usually manifests itself during early childhood at around ages 5–8 years .Characteristic symptoms are increased muscle...
, can be completely treated with regular doses of L-DOPA in a form such as Sinemet (carbidopa/levodopa). Although this doesn't remove the condition, it does alleviate the symptoms most of the time. (In contrast, dopamine antagonist
Dopamine antagonist
A dopamine antagonist is a drug which blocks dopamine receptors by receptor antagonism. There are five known types of dopamine receptors in the human body; they are found in the brain, peripheral nervous system, blood vessels, gastrointestinal tract and the kidney.-Uses and examples:* Used as...
s can sometimes cause dystonia.)
Baclofen
A baclofen
Baclofen
Baclofen is a derivative of gamma-aminobutyric acid . It is primarily used to treat spasticity and is under investigation for the treatment of alcoholism....
pump has been used to treat patients of all ages exhibiting muscle spasticity along with dystonia. The pump delivers baclofen via a catheter to the thecal space surrounding the spinal cord. The pump itself is placed in the abdomen. It can be refilled periodically by access through the skin.
Surgery
Surgery, such as the denervation of selected muscles, may also provide some relief; however, the destruction of nerves in the limbs or brain is not reversible and should only be considered in the most extreme cases. Recently, the procedure of deep brain stimulationDeep brain stimulation
Deep brain stimulation is a surgical treatment involving the implantation of a medical device called a brain pacemaker, which sends electrical impulses to specific parts of the brain...
(DBS) has proven successful in a number of cases of severe generalised dystonia. DBS as treatment for medication-refractory dystonia, on the other hand, may increase the risk of suicide in patients. Unfortunately, reference data of patients without DBS therapy are lacking.
See also
- HypertoniaHypertoniaHypertonia a condition marked by an abnormal increase in muscle tension and a reduced ability of a muscle to stretch. It is caused by lesions to upper motor neurons in the central nervous system, which carry information from the central nervous system to the muscles and control posture, muscle...
- Torsion dystoniaTorsion dystoniaTorsion dystonia is a disease characterized by painful muscle contractions resulting in uncontrollable distortions. This specific type of dystonia is found in children, with symptoms starting around the ages of 11 or 12. It commonly begins with contractions in one general area such as an arm or a...
- Tardive dyskinesiaTardive dyskinesiaTardive dyskinesia is a difficult-to-treat form of dyskinesia that can be tardive...
- Edward FlatauEdward FlatauEdward Flatau was a Polish neurologist. His work greatly influenced the developing field of neurology. He established neurobiologic and neuropathological sciences in Poland...
- Sensory trick
- Sydenham's choreaSydenham's choreaSydenham's chorea or chorea minor is a disease characterized by rapid, uncoordinated jerking movements affecting primarily the face, feet and hands. Sydenham's chorea results from childhood infection with Group A beta-hemolytic Streptococci and is reported to occur in 20-30% of patients with...
- Tyler's Hope for a Dystonia CureTyler's Hope for a Dystonia CureTyler's Hope for a Dystonia Cure is a non-profit foundation based in Gainesville, Florida that raises money and awareness for Dystonia, a neurological movement disorder in which sustained muscle contractions cause twisting and repetitive movements or abnormal postures. was established in 2005 by...
(foundation)
External links
- GeneReview/NIH/UW entry on Dystonia Overview
- Dystonia Society Network Group - for sufferers and carers to share experiences
- Cervical Dystonia Clinical Research Study
- WEGO Health Dystonia Community
- American Dystonia Society
- American Dystonia Society Dystonia Network - Peer Support and Advocacy
- http://www.dfwdystonia.com
- GeneReviews/NCBI/NIH/UW entry on Early-Onset Primary Dystonia
- NSTA
- Dystonia Medical Research Foundation
- Bachmann-Strauss Dystonia & Parkinson Foundation
- The Dystonia Society
- PBSPublic Broadcasting ServiceThe Public Broadcasting Service is an American non-profit public broadcasting television network with 354 member TV stations in the United States which hold collective ownership. Its headquarters is in Arlington, Virginia....
has a Film on Dystonia - A story of one woman's struggle with dystonia at MSNBC.com
- Care4Dystonia Newsletters, Library and Education Forum on Dystonia