Dystonia is a neurological movement disorder that causes muscles in the body to contract or spasm involuntarily. The involuntary muscle contractions cause twisting, repetitive and patterned movements as well as abnormal postures. There are many different types of dystonia and it can affect almost any part of the body.
What is dystonia?
Dystonia is a neurological movement disorder that causes muscles in the body to contract or spasm involuntarily. The involuntary muscle contractions cause twisting, repetitive and patterned movements as well as abnormal postures.
Dystonia is not a single disease but a syndrome – a set of symptoms that cannot be attributed to a single cause but share common elements. Some forms may affect a specific body area, such as the neck, face, jaw, eyes, limbs or vocal cords.
Dystonia is best classified according to the parts of the body affected:
- Focal Dystonia: if only one part of the body is affected, such as the eyes, neck, a limb, or the voice.
- Segmental Dystonia: if a larger region, such as the neck and arms, is involved.
- Hemidystonia: if the spasms affect the arm and leg on the same side.
- Multifocal Dystonia: if two or more unrelated parts of the body are affected.
- Generalised Dystonia: if it is more widespread throughout the body.
Dystonia affects men, women and children of all ages and backgrounds. It can develop in childhood and is often particularly disabling for children. It may be genetic or caused by factors such as physical trauma, exposure to certain medications, or other neurological conditions.
What causes dystonia?
The causes of Dystonia are not yet fully understood, but it is thought that it may be caused by a chemical imbalance in a particular area of the brain called the basal ganglia where the messages to initiate muscle contractions are believed to originate.
The basal ganglia are structures deep in the brain that are, in part, responsible for controlling movement. They regulate the numerous muscle contractions that are necessary to move the body. If this part of the brain is damaged in some way, the wrong muscles contract when we try to move. Or the muscles contract unnecessarily even when we are immobile, causing uncontrollable twitching, tremors and contractions. These spasms are known as dystonic movements.
Some patients may have suffered from an illness or injury which has damaged the basal ganglia, but in the majority of cases, the underlying cause of the condition is unknown. If no cause can be pinpointed, the dystonia is said to be idiopathic. Depending upon the type of dystonia, the specialist may decide to carry out blood tests or scans in an attempt to determine the cause.
Genetic component
The fact that dystonia sometimes affects more than one member of a family makes it clear that inheritance can play an important role. Most cases of primary, segmental and generalised dystonia are due to a gene inherited in a dominant manner. Many cases of dopa-responsive dystonia are inherited in this way. Dominant means that each child of a parent who carries the abnormal gene has a 50/50 chance of inheriting that gene.
A number of different genes on different chromosomes have now been identified as being linked with different types of dystonia, but researchers don’t yet know exactly how a particular gene causes dystonia. The DYT1 gene on chromosome 9, which is related to early-onset generalised dystonia, was only located in 1997. One benefit of finding this single mutation for familial dystonia is that genetic counselling and testing will in future be available for appropriate individuals. Patients should seek specialist advice from a neurologist about the risks to their relatives, based on the details of each individual case. As with all genetic research, the next step will be to work out what the function of the gene is, and how it causes dystonia.
Diagnosis
Currently, there is no specific laboratory test or imaging that reliably confirms a diagnosis of dystonia. Instead, the diagnosis of dystonia rests largely on the clinical picture, including the patient’s account of symptoms, their medical background and the physical examination. For a doctor to diagnose a form of dystonia, they need to be able to recognise the physical signs and be familiar with the symptoms. Further tests may be ordered, but in many cases these will be normal.
Why haven’t I heard of dystonia before?
It was only halfway through the last century that dystonia was recognised as a physical (organic) condition, and different forms were identified as manifestations of the same illness. In spite of this, dystonia often remains misunderstood and misdiagnosed. Research from the United States indicates that dystonia is as common as multiple sclerosis in certain areas of the world, including parts of Australia. However, there is little literature that provides adequate information about dystonia or explains its effects on those who live with the condition.
Treating dystonia
A Specialist Neurologist who has a special interest in movement disorders is the best person to diagnose, treat and understand your special needs. Your General Practitioner (GP) will be able to refer you to one of these specialists.
Botox
For focal dystonias, including blepharospasm, spasmodic torticollis, oromandibular dystonia, spasmodic dysphonia and sometimes writer’s cramp, injections of botulinum toxin to temporarily weaken the muscles involved have become a very effective treatment. Botulinum toxin is usually most effective if the dystonia affects only a limited group of muscles. Generally, the injections need to be repeated every 3 or 4 months, though this may vary from patient to patient. The injections are available in certain neurology, ophthalmology and ENT clinics.
Physiotherapy
It is now being recognised that some specialised types of physiotherapy can help – usually in association with botulinum toxin – especially for patients with torticollis. Speech therapy has been shown to prolong the effects of Botulinum toxin by reducing compensatory speech patterns. Many other types of treatment have been tried.
Medication
If the problem is mild, it may be best to avoid drug treatment. Drugs need to be taken continuously for long periods of time, and all drugs can cause unwanted side effects. No drugs can cure dystonia yet.
However, if your dystonia is causing unacceptable disability, then drug treatment may be recommended to try to control the muscle spasms. Unfortunately, drug treatment is scarcely ever 100% effective, and many patients do not get great relief. Another problem is that no one drug is best for all patients with dystonia. Children usually respond better, but if one drug doesn’t work, you may need to try a series of different drugs to discover which is best for you, offering the greatest relief but producing the fewest side effects.
Surgery
In the past, surgical options have included selective cervical denervation, thalamotomy, and pallidotomy. The growing adoption of deep brain stimulation for the treatment of intractable movement disorders has led to the emergence of pallidal stimulation as the surgical therapy of choice for many patients with dystonia. Published series have supported the efficacy of chronic globus pallidus internus (GPi) stimulation in the treatment of this group of abnormal involuntary movement disorders, however, the long-term outcome and pattern of clinical improvement is yet to be ascertained.
Alternative treatments
Unfortunately, there is little evidence that acupuncture, homoeopathy, or diet produce any lasting benefit. Some patients, however, do feel that such treatments lessen stress, which in turn can reduce muscle spasms.
Outlook
If dystonia develops in childhood, particularly if it starts in the legs, then in many (but not all) cases it will spread to other parts of the body and become generalised. However, when it develops in adults, it tends to have different characteristics, is generally confined to a local area (focal dystonia) and is less likely to spread to other parts of the body.
Common Forms of Dystonia
Cervical Dystonia
Cervical Dystonia, often referred to as spasmodic torticollis, is a particular type of focal dystonia that affects the muscles of the neck. The muscle spasms can be painful and cause the neck to twist to one side (torticollis), forward (anterocollis), or backward (retrocollis). The neck may pull, turn or jerk; it may be held persistently in one direction. Read more >
Blepharospasm
This is a condition where the eyelid muscles spasm, causing the eyelids to close suddenly without warning. The individual has difficulty opening them again and, if severe, can lead to problems with sight, although vision is not affected. Blepharospasm is often aggravated by sunlight. Read more >
Oromandibular Dystonia
Oromandibular Dystonia can affect the face, tongue, palate and jaw and presents with abnormal mouth or tongue movements, grimacing or forced opening or closing of the mouth.
Hand Dystonia (Including Writer’s Cramp)
Hand Dystonia affects the muscles in the fingers, hand, wrist, and sometimes the forearm or shoulder. It is usually task-specific or related to the person’s occupation, and the most common form is writer’s cramp. Writer’s cramp causes the fingers to cramp, rotate, or assume an abnormal posture when the patient attempts to write. Hand dystonia is also common for musicians and typists. Symptoms can vary depending on the actions involved, and can affect accuracy, hand positioning, involuntary flexion of the fingers, and more. However, some patients are only affected when they attempt the specific task, and the use of their hand could be otherwise unimpaired. This is difficult to treat as there may be many small muscles in the hand and forearm involved. Individuals may choose to learn to use their non-dominant hand.
Spasmodic Dysphonia
Spasmodic Dysphonia, sometimes known as Laryngeal Dystonia, is a rare voice disorder. Overactive movement of the muscles of the larynx (excessive closure or opening of the vocal cords) occurs during specific vocal activities such as speaking but not during laughing or yawning. The voice may be strained and effortful with sudden interruptions causing momentary loss of voice. Dysphonia can be seen with other focal dystonias such as oromandibular dystonia and blepharospasm. Read more >
Meiges’ Syndrome
Meiges’ Syndrome, also known as Breughel’s disease, from the 16th century Flemish painter who captured the syndrome on canvas. Meiges’ is a combination primarily of blepharospasm and oromandibular Dystonia but may be seen with dysphonia.
Hemidystonia
Hemidystonia means muscle groups on one side of the body are affected, causing loss of balance and difficulty moving around. There is a lot of strain put on the unaffected muscles.
Generalised Dystonia
Generalised Dystonia is a rare form of dystonia which is seen more often in children than in adults. It is generally a severe disability, affecting areas of the body. Generalised dystonia often starts in a lower limb, then spreads to other areas such as the neck, limbs and trunk. People with generalised dystonia often have a genetic basis for their disease.
Other Forms of Primary Dystonia
Dopa-Responsive Dystonia (DRD)
Dopa-responsive Dystonia (DRD) is a broad term used to describe cases of Dystonia that respond dramatically to low doses of a medication called levodopa. DRD usually starts in childhood or adolescence with progressive difficulty in walking. It may be misdiagnosed as cerebral palsy or parkinsonism. Several genes have been associated with Dopa-responsive Dystonia.
Myoclonic Dystonia
Myoclonic Dystonia (hereditary essential myoclonus), often mistaken for essential tremor, is characterised by rapid jerking movements alone or in combination with the sustained muscular contractions and postures of dystonia. The symptom distribution of myoclonic dystonia is different from typical early-onset dystonia as it more often affects the upper body, whereas typical early-onset dystonia usually affects the legs. A gene associated with myoclonus dystonia has been identified.
Rapid-onset Dystonia-Parkinsonism (RDP)
Rapid-onset dystonia-parkinsonism (RDP) is characterised by the abrupt onset of slowness of movement (parkinsonism) and dystonic symptoms. The classic features of RDP include involuntary dystonic spasms in the limbs, prominent involvement of the speech and swallowing muscles, slowness of movement and poor balance. Onset of the combined dystonic and parkinsonian symptoms can be sudden, occurring over hours to days. RDP usually occurs in adolescence or young adulthood (age range 15 to 45).
Paroxysmal Dystonia and Dyskinesias (PDD)
Paroxysmal Dystonia and Dyskinesias (PDD) are a group of disorders in which the patient experiences relatively brief episodes of abnormal movements and postures with a return to normal posture between episodes. Some forms of PDD are genetic.
X-linked Dystonia-Parkinsonism (lubag)
X-linked dystonia-parkinsonism (Lubag) is a form of dystonia found almost exclusively among men originally from the Philippine island of Panay. Female family members are carriers of the gene. X-linked dystonia-parkinsonism usually begins focally, generalises, and may be replaced by parkinsonian features.
Secondary (Symptomatic) Dystonia
In this type of Dystonia, the symptoms are due to small areas of brain damage. The dystonia is segmental, generalised or hemidystonia. The damage can be caused by reduced oxygen around the time of birth or in utero (cerebral palsy), by other injury to the brain, small strokes or tumours. Secondary dystonia usually results from apparent outside factors such as exposure to certain medications, trauma, toxins or infections. Dystonia can also be secondary to other illnesses that affect the nervous system such as Wilson’s disease, Huntington’s disease and multiple sclerosis.
Related Disorders
Secondary dystonias can accompany other disorders, resulting in dystonic symptoms.
Wilson’s Disease
Wilson’s Disease (hepatenticular degeneration) is a rare hereditary disease resulting from excessive copper accumulation in the body. Normally, copper is excreted without any difficulties, but in Wilson’s disease, copper is deposited and accumulates in the liver, brain and around the eye. Dystonia is a prominent clinical feature in some people with Wilson’s disease. Wilson’s disease requires specific treatment.
Hallervorden-Spatz Disease
Officially renamed Pantothenate Kinase-Associated Neurodegeneration or PKAN
PKAN is a very rare inherited progressive disease of the brain, typically involving the basal ganglia and often associated with severe dystonia and parkinsonism. An MRI scan of the brain is very helpful in making the diagnosis of PKN by demonstrating increased iron deposition in these deep brain regions.
Recent Research Grants
2022 – MRI guided focused ultrasound (MRgFUS) for focal hand dystonia – Dr Joel Maamary – Read more >
2019 – MRI cervical muscles in chronic migraine and cervical dystonia – Dr Lin Zhang – Read more >
Further information and support:
Information
- Living with Dystonia & Participating in Research | Steph’s Story
- Living with Dystonia | Margot’s Story
- Dystonia Webinar – Dr Florence Chang, 2016 | Watch here
Support
- Dystonia Network of Australia – https://dystonia.org.au/
- Australian Dystonia Support Group – http://australiandystoniasupportgroup.wordpress.com/
- Dysphonia International – https://dysphonia.org/about-us/
DISCLAIMER: The information provided is designed to support, not replace, the relationship that exists between a patient / site visitor and his / her existing health care professionals.
The Brain Foundation is dedicated to funding the next generation of Australian research into brain disorders, diseases, and injuries, with the ultimate goal of advancing diagnoses, treatments, and patient outcomes.