Dystonia Overview:
Dystonia is a neurological movement disorder in which sustained muscle contractions cause twisting and repetitive movements or abnormal postures. Dystonia is characterized by long-lasting (sustained) involuntary muscle contractions that may force people into abnormal positions—for example, causing the entire body, the trunk, limbs, or neck to twist. Movements are usually patterned and twisting, and may resemble a tremor.
Dystonia is often initiated or worsened by voluntary movements, and symptoms may “overflow” into adjacent muscles. Dystonia is classified multiple clinical characteristics including age of onset, body distribution, nature of the symptoms, and associated features such as additional movement disorders or neurological symptoms and cause which includes changes or damage to the nervous system and inheritance factors.
There are multiple forms of dystonia, and dozens of diseases and conditions may include dystonia as a symptom. Dystonia may affect a single body area or be generalized throughout multiple muscle groups. Dystonia affects men, women, and children of all ages and backgrounds. Dystonia causes varying degrees of disability and pain, from mild to severe. There is not yet a cure, but multiple treatment options exist and scientists around the world are actively pursuing research toward new therapies.
The condition can affect one part of your body (focal dystonia), two or more adjacent parts (segmental dystonia) or all parts of your body (general dystonia). The muscle spasms can be mild or severe, and might interfere with your performance of day-to-day tasks.
Although there are several forms of dystonia and the symptoms may outwardly appear quite different, the element that all forms share is the repetitive, patterned, and often twisting involuntary muscle contractions. Dystonia is a chronic disorder, but the vast majority of dystonias do not impact cognition, intelligence, or shorten a person’s life span.
Other forms of muscle tone symptoms include:
Hypotonia: An abnormally low muscle tone, is by itself not a disorder but a symptom of an enormous array of issues—many of which can be difficult to diagnose accurately. Even in the absence of a specific underlying diagnosis, however, children with hypotonia can benefit from clinical intervention.
Hypertonia: A condition in which there is too much muscle tone so that arms or legs, for example, are stiff and difficult to move.
Dystonia Classifications
Primary (idiopathic) – dystonia is the only sign, and secondary causes have been ruled out. Most primary dystonias are variable, have adult onset, and are focal or segmental in nature. However, there are specific primary dystonias with childhood or adolescent onset that have been linked to genetic mutations.
Secondary (symptomatic) – dystonia that results primarily from secondary causes. These include environmental, such as exposure to carbon monoxide, cyanide, manganese, or methanol; underlying conditions and diseases such as brain tumors, cerebral palsy, Parkinson’s disease, stroke, multiple sclerosis, hypoparathyroidism, or vascular malformations; brain/spinal cord injuries; inflammatory, infectious, or postinfectious brain conditions; and specific medications.
Dystonia-plus syndromes – dystonia that results from nondegenerative, neurochemical disorders associated with other neurological conditions. Dystonia-plus syndromes include dopa-responsive dystonia (DRD) or Segawa syndrome, rapid-onset dystonia-parkinsonism (RDP), and myoclonus-dystonia.
Heredodegenerative dystonia – dystonia that generally results from neurodegenerative disorders in which other neurological symptoms are present and in which heredity plays a role. These include numerous disorders such as certain X-linked recessive, autosomal dominant, autosomal recessive, and/or parkinsonian syndromes. Included in this category: X-linked dystonia-parkinsonism (Lubag), Huntington’s disease, Wilson’s disease, neuroacanthocytosis, Rett’s syndrome, Parkinson’s disease, and juvenile parkinsonism.
General Dystonia Symptoms:
Dystonia affects different people in varying ways.
Muscle contractions might:
- Begin in a single area, such as your leg, neck or arm. Focal dystonia that begins after age 21 usually starts in the neck, arm or face and tends to remain focal or segmental.
- Occur during a specific action, such as handwriting.
- Worsen with stress, fatigue or anxiety.
- Become more noticeable over time.
- Neck (cervical dystonia). Contractions cause your head to twist and turn to one side, or pull forward or backward, sometimes causing pain.
- Eyelids. Rapid blinking or involuntary spasms causing your eyes to close (blepharospasms) can make you functionally blind. Spasms usually aren’t painful, but might increase when you’re in bright light, under stress or interacting with people. Your eyes might feel dry.
- Jaw or tongue (oromandibular dystonia). You might experience slurred speech, drooling, and difficulty chewing or swallowing. Oromandibular dystonia can be painful and often occurs in combination with cervical dystonia or blepharospasms.
- Voice box and vocal cords (spasmodic dystonia). You might have a tight or whispering voice.
- Hand and forearm. Some types of dystonia occur only while you do a repetitive activity, such as writing (writer’s dystonia) or playing a specific musical instrument (musician’s dystonia).
Types of Dystonias and Symptoms:
Dystonias may affect one part (focal dystonias) or several parts (segmental dystonias) of the body. Sometimes they affect the whole body (generalized dystonias).
Focal and segmental dystonias:
Dystonias that affect one or several body parts typically start in a person’s 30s but sometimes start earlier. Initially, contractions (spasms) may occur periodically or only during stress. Certain movements of the affected body part may trigger the spasms, which may disappear during rest. Over days, weeks, or many years, spasms may become more frequent and may continue during rest. Eventually, the affected body part may remain distorted, sometimes in a painful position. As a result, people may be severely disabled.
The following are examples of focal or segmental dystonias:
Blepharospasm: This dystonia affects mainly the eyelids. The eyelids are repeatedly and involuntarily forced shut. Occasionally, only one eye is affected at first, but ultimately, the other eye is also affected. It usually begins as excessive blinking, eye irritation, or extreme sensitivity to bright light. Many people with blepharospasm find ways to keep their eyes open, such as yawning, singing, or opening the mouth wide. These techniques become less effective as the disorder progresses. Blepharospasm can severely impair vision if the eyes cannot be kept open as needed.
Spasmodic torticollis: Torticollis specifically affects the muscles of the neck. Spasmodic torticollis, also called adult-onset cervical dystonia, is the most common form of cervical dystonia, which is the most common dystonia of the neck (see Cervical Dystonia).
Spasmodic dysphonia: The muscles of the vocal cords, which control speech, contract involuntarily. Speech may be impossible or may sound strained, quavery, hoarse, whispery, jerky, creaky, staccato, or garbled and be difficult to understand.
Occupational dystonias: These dystonias, also called task-specific dystonias, affect one part of the body and often result from overuse. For example, golfers may have involuntary muscle spasms in the hands and wrists (called the yips). The yips may make putting nearly impossible. What is supposed to be a 3-foot putt can become a 15-foot putt when a golfer loses control because of the yips. Similarly, musicians, especially concert pianists, may have bizarre spasms of the fingers, hands, or arms that prevent them from performing. Musicians who play wind instruments may have spasms of the mouth. Persistent writer’s cramp may be dystonia.
Meige disease: This dystonia combines involuntary blinking with jaw grinding and grimacing. Thus, it is also called blepharospasm-oromandibular dystonia. (“Blepharo” refers to the eyelids, “oro” refers to the mouth, and “mandibular” refers to the jaw.) It usually begins in late middle age.
Generalized dystonias:
Dystonias that affect the whole body include the following:
Generalized dystonia: This rare dystonia, also called idiopathic torsion dystonia, is progressive and often hereditary. In many cases, specific genetic mutations have been identified. The gene most commonly affected is the DYT1 gene. The resulting dystonia is called DYT1 dystonia. Involuntary movements result in sustained, often bizarre postures. Typically, symptoms begin during childhood, often with turning the foot in during walking. The dystonia may affect only the trunk or a leg but sometimes affects the whole body, ultimately confining children to a wheelchair. When this dystonia develops in adults, it usually begins in the face or arms and usually does not affect other parts of the body. Mental function is not affected.
Dopa-responsive dystonia: This rare form of dystonia is hereditary. Symptoms usually begin during childhood. Typically, one leg is affected first. As a result, children tend to walk on tiptoes. Symptoms worsen at night. Walking becomes progressively more difficult, and both arms and legs are affected. However, some children have only mild symptoms, such as muscle cramps after exercise. Sometimes symptoms appear later in life and resemble those of Parkinson disease. Movements may be slow, balance may be difficult to maintain, and a tremor may occur in the hands during rest. Symptoms lessen dramatically when people are given low doses of levodopa. If levodopa relieves the symptoms, the diagnosis is confirmed.
Causes of Dystonia:
The exact cause of dystonia is not known. But it might involve altered nerve-cell communication in several regions of the brain. Some forms of dystonia are inherited.
Dystonia also can be a symptom of another disease or condition, including:
- Parkinson’s disease
- Multiple sclerosis
- Huntington’s disease
- Wilson’s disease
- Traumatic brain injury
- Birth injury
- Stroke
- Brain tumor or certain disorders that develop in some people with cancer (paraneoplastic syndromes)
- Oxygen deprivation or carbon monoxide poisoning
- Infections, such as tuberculosis or encephalitis
- Reactions to certain medications or heavy metal poisoning
Diagnosing Dystonia:
At this time, there is no single test to confirm the diagnosis of dystonia. Instead, the diagnosis rests in a physician’s ability to observe symptoms of dystonia and obtain a thorough patient history. In order to correctly diagnose dystonia, doctors must be able to recognize the physical signs and be familiar with the symptoms. In certain instances, tests may be ordered to rule out other conditions or disorders. The kind of specialist who typically has the training to diagnose and treat dystonia is a movement disorder neurologist.
The dystonia diagnostic process may include:
- Patient history
- Family history
- Laboratory studies such as blood and urine tests, and analysis of cerebrospinal fluid
- MRI or CT scan. These imaging tests can identify abnormalities in your brain, such as tumors, lesions or evidence of a stroke.
- Electrical recording techniques, such as electromyography (EMG) or electroencephalography (EEG)
- Genetic testing for specific forms of dystonia
- Other tests and screenings intended to rule out other conditions or disorders
Treating Dystonia:
To manage your muscle contractions, your doctor might recommend a combination of medications, therapy or surgery.
Medications
Botulinum toxin (Botox) that’s injected into specific muscles might reduce or eliminate your muscle contractions and improve your abnormal postures. Injections are usually repeated every three to four months.
Other medications target signaling chemicals in your brain (neurotransmitters) that affect muscle movement.
The options include:
- Carbidopa-levodopa (Parcopa, Sinemet). This combination medication can increase levels of the neurotransmitter dopamine.
- Trihexyphenidyl, benztropine. These medications act on other neurotransmitters. Side effects can include memory loss, blurred vision, drowsiness, dry mouth and constipation.
- Tetrabenazine (Xenazine). This medication blocks dopamine. Side effects can include sedation, nervousness, depression or insomnia.
- Diazepam (Valium), clonazepam (Klonopin), baclofen (Lioresal). These medications reduce neurotransmission and might help some forms of dystonia. These medications may cause side effects, such as drowsiness.
Therapy
Your doctor might suggest:
- Physical therapy to help ease your symptoms
- Speech therapy if dystonia affects your voice
- Stretching or massage to ease muscle pain
- Sensory tricks that involve touching your affected body part, which might help reduce your contractions
Surgery
If your symptoms are severe, your doctor might recommend:
- Deep brain stimulation. Electrodes are surgically implanted into a specific part of your brain and connected to a generator implanted in your chest. The generator sends electrical pulses to your brain that might help control your muscle contractions. The settings on the generator can be adjusted to treat your specific condition.
- Selective denervation surgery. This procedure, which involves cutting the nerves that control muscle spasms, might be an option to treat some types of dystonia that haven’t been successfully treated using other therapies.
Alternative medicine
Alternative treatments for dystonia haven’t been well-studied. Ask your doctor about complementary treatments before you start.
Consider:
- Meditation and deep breathing. Both might ease stress that can worsen spasms.
- Biofeedback. Electronic devices monitor your body’s functions, such as muscle tension, heart rate and blood pressure. You then learn how to control your body responses, which might help reduce muscle tension and stress.
- Yoga. Yoga combines physical postures, breathing techniques, and meditation or relaxation.
- Stretching or massage. These can ease muscle pain.
Home therapies that may help
- Sensory tricks to reduce spasms. Touching certain parts of your body may cause spasms to stop temporarily.
- Stress reduction. Try to avoid stressful situations because stress tends to make your symptoms worse.
- Heat or cold. Applying heat or cold can help ease muscle pain.
