Dystonia

Muscle contractions in the neck can be a symptom

Dystonia is an incurable neurological movement disorder thought to affect at least 40,000 in the UK alone.

What is dystonia?

Dystonia is the term used to describe a condition that causes involuntary sustained muscle contractions that lead to abnormal movements and postures.

It is a neurological disorder but does not lead to problems with other functions of the brain such as intellect.

How many different types of dystonia are there?

Focal dystonias are the most common form and affect only one part of the body. They include:

Cervical dystonia (spasmodic torticollis): Dystonia of the neck muscles which causes the head to twist, pull in one direction, or shake.

Blepharospasm: Dystonia of the muscles around the eyes

Oromandibular dystonia: Dystonia affecting the muscles of the jaw, tongue and mouth

Laryngeal dystonia: Dystonia affecting the speech muscles

Writer's cramp: Dystonia affecting the ability to write and sometimes other hand-based tasks

There are other types of dystonia that affect more than one area, including generalised dystonia that affects most of the body, frequently involving the legs and back (trunk).

Who is affected by dystonia?

Dystonia affects men and women of all ages.

If it develops in childhood, it tends to become generalised.

Dystonia which has its onset in adult life usually remains focal and is more common in those over 40 years of age.

The condition can be difficult to diagnose and many patients remain untreated because their symptoms are unrecognised.

It is thought that there are more than 40,000 people with dystonia in the UK.

What are the causes of dystonia?

The causes of dystonia are still not fully understood, but there appears to be a problem in an area of the brain called the basal ganglia, involved in controlling movement.

It has been suggested that an imbalance of neurotransmitters (such as dopamine) leads to this defect in control of muscles and movement.

In some cases, damage to the basal ganglia can lead to dystonia.

These are referred to as secondary dystonia and can be due to a variety of causes such as stroke or tumour of the basal ganglia, or the result of certain drugs (especially dopamine blocking drugs used to treat psychiatric disorders) and so on.

In the majority of cases, no underlying cause is found apart from possible genetic factors, and these are called primary or idiopathic dystonia.

Is it inherited?

Dystonia that develops in childhood is often inherited through one or more affected genes.

Most primary segmental or generalised dystonia is inherited in a dominant manner, which means that if a parent has this type of dystonia, there is a 50% chance of passing the dystonia gene to each child.

However, not everyone who inherits the gene develops dystonia, a phenomenon known as reduced penetrance.

Dystonia which develops in adults may also be inherited.

This is often difficult to identify, since other family members may have only a mild form of the illness. They may have never sought medical advice or perhaps their dystonia was misdiagnosed.

What should I do if I think I have dystonia?

If you think you may have dystonia and it has not yet been diagnosed, you should see your doctor and ask to be referred to a neurologist specialising in movement disorders.

If you are diagnosed as having blepharospasm, you may be treated by an ophthalmologist.

If you have laryngeal dystonia, you may see an ear, nose and throat (ENT) specialist.

Will my dystonia improve?

In many cases, if dystonia develops in childhood, particularly if it starts in the legs, it may spread to other parts of the body and can become generalised.

However, when it develops in adults, it usually confines itself to one part of the body (focal dystonia).

The progress of dystonia is unpredictable.

The severity of symptoms can vary from day to day, and while there often is an element of overall progression, it is difficult to estimate how long this will last.

Typically, a focal dystonia will progress very gradually over a five-year period, and then progress no further.

Symptoms in all dystonic conditions can vary.

For some people, their dystonia may sometimes improve or disappear altogether for no apparent reason.

Is there a cure for dystonia?

Unfortunately, there is not yet a cure for most forms of dystonia.

Nowadays, however, many dystonic conditions can be very successfully managed.

How do I live with dystonia?

As with the onset of any long-term medical condition, some people who develop dystonia may go through an initial period of depression, embarrassment and outrage - or relief that there is an explanation for their symptoms.

Most people do manage to develop effective strategies for coping with the challenges that their condition brings.

Successful treatments to lessen their symptoms, effective pain control and the acquisition of sensory 'tricks' all help to ameliorate social situations.

What forms of treatment are available?

Various treatments are available for dystonia. These will be determined depending upon the type and severity of the particular condition.

The main options are:

Botulinum Toxin: Injections are generally the most effective treatment for dystonia where it affects the muscles of the neck or around the eyes.

Drugs: Drugs are effective for some patients. Some work by interfering with neurotransmitters, the chemical substances that carry messages within the brain.

Others are designed to relax the muscles, reducing shaking and control muscle spasms.

To be effective, they have to be taken continuously.

Surgery: Surgery may be an option where patients have never been or are no longer receptive to other treatments.

(Resistance to botulinum toxin can develop in a minority of patients over a period of time). Surgical treatments include selective denervation and deep brain stimulation (DBS.

In the case of the latter, electrodes are planted in the basal ganglia to help 'rebalance' movement and to control posture.

Some recent research has led to a refinement in the placing of electrodes for optimum effect.

Does it have a low profile?

Yes. Even though dystonia is estimated to be about ten times more common than motor neurone disease, many people have never heard of it.

Indeed, until recently, many GPs were unfamiliar with the condition.

However, in the last few years, awareness of dystonia has increased and the outlook for people with dystonia is improving.

The Dystonia Society, a registered charity, works hard to speed up the processes of both research and recognition.