What is dystonia?
Our brain essentially controls our movements via special groups of nerves. In dystonia, this function is impaired for various reasons. This means that there is a nerve disorder.
As a result, individual muscles or muscle groups contract involuntarily. These muscle contractions are comparable to a muscle cramp. Those affected notice this through unusual movements and postures, which can occur briefly or permanently. Doctors therefore also classify dystonia as a movement disorder.
The term dystonia means “dysregulated tension” from the Greek “dys” = “dysregulated” and “tonus” = tension.
Dystonia includes various forms:
Generalized dystonia
In this case, the muscle cramps extend to larger areas or even the entire body. Generalized dystonia is usually inherited. It often begins in childhood or adolescence and can result in severe disabilities. Generalized dystonia can also occur in connection with another underlying disease. In this case, it is also referred to as symptomatic dystonia.
Focal dystonia
This form only affects individual muscle groups or one region of the body. If two neighboring muscle groups are involved, this is referred to as segmental dystonia. In multifocal dystonia, several non-adjacent muscle groups are affected.
Specialists differentiate between several subtypes of focal dystonia, depending on which muscles are mainly affected:
- Torticollis: Dystonia in the neck area can lead to a certain head misalignment, known as torticollis. This form is also known as cervical dystonia or torticollis spasmodicus. Torticollis is one of the most common focal dystonias and occurs in around three out of four people affected. Torticollis can be caused by a nerve disorder or muscle damage (neurological disorder) at birth. Different head postures occur depending on the muscles affected. It is typical for those affected to tilt their head to the side in the direction of the tense muscle.
- Eyelid spasm: Eyelid spasm, also known as blepharospasm, is the second most common form of focal dystonia and affects women more often than men. The function of a ring muscle (orbicularis oculi muscle) running around the eyes is impaired. This causes those affected to involuntarily squint one or both eyes. The symptoms often worsen in bright light, watching television or in the wind. Eyelid spasm temporarily restricts vision and can affect those affected, particularly when driving.
- Vocal cord spasm: If muscle contractions occur in the vocal cord muscles, this is referred to as vocal cord spasm or spasmodic dysphonia or laryngeal dystonia. Depending on the muscles involved, the voice may sound strained, squeezed and sometimes very quiet. Some sufferers only have problems with speaking, but not with singing or laughing.
- Writer’s cramp: An action-specific focal dystonia or occupational dystonia only occurs during certain activities. It is most frequently seen in handwriting. Those affected seem to literally squeeze the pen with their fingers. If initially only the muscles of the hand are affected, the muscles of the arm can also be affected as the disease progresses. This form can also affect musicians such as pianists.
- Mouth, tongue and pharyngeal spasm: If the facial muscles are affected, twitching and spasms of the facial muscles can distort the face like a grimace. As a result, patients with oromandibular dystonia often avoid contact with other people. Sometimes the cramps can also affect food intake.
Dystonia – frequency and age
Dystonia is one of the rare diseases. Experts estimate that around 40 out of every 100,000 people suffer from dystonia.
Depending on the form of the disease, dystonia can occur at any age. Generalized dystonia often begins in childhood and adolescence. In contrast, focal dystonia usually occurs between the ages of 30 and 50.
Dystonia: causes and risk factors
In most cases it is an idiopathic (primary) dystonia. This means that the exact causes are not known.
Secondary dystonia occurs less frequently, but can have numerous causes. These include
- Huntington’s disease (hereditary disease of the brain)
- certain forms of Parkinson’s disease
- Rare metabolic diseases
- infectious diseases
A common known cause of secondary dystonia is the side effects of certain medications (neuroleptics). These can lead to incorrect movements – so-called early and late dyskinesias. Accidents with injuries in the neck area are also a possible cause.
In the past, focal dystonia was considered to have psychological causes. It is now assumed to be an organic disease with physical causes. It is known that the basal ganglia are particularly impaired in dystonia. Basal ganglia are collections of nerve cells that are important for the coordination of movement sequences.
Symptoms: Dystonia
The symptoms can vary greatly depending on the form and severity of the dystonia.
The involuntary muscle contractions can only occur in individual areas of the body, such as the neck, arms and legs, or over the entire body. Some sufferers only have mild symptoms and are therefore hardly restricted in their everyday lives. Others, however, suffer from severe pain or can only perform certain movements with difficulty. The affected muscles are usually thickened and protrude visibly.
Early symptoms of torticollis or a tilted head can be tension and tremors. Those affected can often stop the tension by making certain movements – for example, by placing a finger on their chin. Initially, the cramp-like movements subside after a while. However, they can occur permanently as the disease progresses. Some sufferers also suffer from depressive moods because the muscle contractions force them to make strange movements and postures. This can be a great emotional burden.
Dystonia: Diagnosis with us
If dystonia is suspected, we will question the affected person in detail. This so-called anamnesis and a subsequent thorough physical examination often provide important clues for the diagnosis.
In some cases, further examinations such as measuring the electrical activity of muscle fibers (electromyography, EMG), blood and urine tests and magnetic resonance imaging (MRI) of the head can confirm the diagnosis.
Dystonia: prevention, early detection, prognosis
Generalized dystonia can be hereditary. Prevention is therefore not possible. The same applies to the various forms of focal dystonia, the causes of which are still unknown. This makes it all the more important for dystonia to be recognized in good time and for targeted treatment to take place.
Course and prognosis of dystonia
Dystonia can progress in very different ways. In some patients, the symptoms disappear completely within the first three years (remission). However, the dystonia may reoccur later. In other cases, the symptoms increase steadily over three to five years before the clinical picture stabilizes. The pain is often problematic and can increase regardless of the severity of the dystonia. Poor posture often puts a strain on the joints. This can lead to joint problems.
Self-help groups
The exchange with people who are affected by the same disease can be a great support in coping with the disease. Advice on finding a suitable self-help group is available from
Selbsthilfe Zürich. Self-Help Zurich and the University Hospital Zurich are cooperation partners in the national project “Health literacy thanks to self-help-friendly hospitals”.
Dystonia: treatment depending on form and symptoms
In many cases, the causes of dystonia are unknown. As a result, there is currently no causal or curative therapy and treatment is aimed at alleviating symptoms and maintaining quality of life.
Dystonia can be treated on an outpatient basis by neurological specialists or in a special center (movement outpatient clinic). There are several options available for this. Which therapy is suitable depends primarily on the form of the disease.