Focal dystonia, can affect the hands, so that the fingers curl into the palm or extend outward without control.
Focal dystonia is unusual, but it is one of the most common neurological conditions. In the United States, 30 in every 100,000 people are thought to live with it. It can affect people of all ages, including children, but symptoms most commonly begin between the ages of 40 and 60 years.
Dystonia is a movement disorder.
Dystonia refers to a syndrome of disordered movement. There are many types of dystonia, and they can affect various muscles in the body, depending on the type.
Symptoms vary according to the kind of dystonia involved. Cervical dystonia, or torticollis, occurs in the neck. It is the most common form of focal dystonia. There is also upper limb, lower limb, and even lingual dystonia.
Since there are many kinds of movement disorder, dystonia can be classified in various ways, for example, by age of onset, where it occurs in the body, or if it is a primary or secondary condition.
Early symptoms of focal dystonia may include a loss of precision in muscle coordination.
The individual may first notice that they have increasing difficulty in using a pen, they experience frequent small injuries to the hands. They may become more likely to drop items.
Sustained use of a muscle may lead to a cramping pain and trembling.
Significant muscle pain and cramping may result from minor exertions like holding a book and turning pages.
As well as direct symptoms, patients may experience secondary effects on continuous muscle and brain activity.
These can include 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, as their condition worsens, they may find it difficult to carry out their daily activities.
Some patients have symptoms that get worse and then stabilize for years. In other cases, symptoms may stop progressing entirely.
Symptoms may be slowed by treatment or through lifestyle changes. If the patient continues to use their muscles in the same way as previously, symptoms can progress more rapidly.
Primary dystonia is thought to happen when the basal ganglia do not produce enough neurotransmitters, or when it produces the wrong kind of neurotransmitters. It is sometimes hereditary.
Musicians are prone to some kinds of focal dystonia.
The basal ganglia is a collection of brain cells at the front of the brain. They are responsible for sending messages from the brain to various muscles in order to move them.
Secondary dystonia can be the result of another neurological condition, or it may be triggered by known environmental cause. These might be a birth injury that leads to hypoxia or neonatal brain hemorrhage, or trauma or stroke later in life.
Focal dystonia has been linked to environmental and task-related factors.
People who perform high precision hand movements, such as musicians, engineers, architects, and artists are statistically more likely to develop it. One form of the condition is sometimes called "musician's dystonia."
It also tends to be "task specific." This means that it only poses a problem during certain activities.
Other risk factors include anxiety or "choking" that many athletes experience during high-stress competition and overuse of the muscles involved in fine-motor control and precise movements.
Sometimes a patient who already has a neurological condition, such as Parkinson's, Huntington's, or Wilson's disease, may develop secondary focal dystonia.
Parkinson's happens when there is a lack of dopamine, which is a neurotransmitter. Huntington's is an inherited condition in which the patient does not have enough cholesterol in the brain. Wilson's disease is a genetic condition that causes copper to build up in the tissues of the body.
It is important to confirm whether a case of dystonia is primary or secondary, because the underlying cause will dictate the kind of treatment that is suitable.
Treating a primary condition, such as Parkinson's, may help to decrease levels of focal dystonia.
Electromyography (EMG) is a procedure that uses electrical sensors to help provide a definitive diagnosis of focal dystonia. The sensors are inserted into the affected muscle groups, and they show pulsating nerve signals being transmitted to the muscles even when the muscles are at rest.
When called upon to perform an intentional activity, the muscles tire very quickly, and some parts of the muscle groups do not respond, causing weakness. Other portions may over-respond or become rigid.
This test can diagnose more severe focal dystonia, but it can be painful.
Lifestyle changes may be necessary, to reduce the types of movement likely to trigger or worsen dystonic symptoms. This can provide some relief. Reducing stress, getting plenty of rest, moderate exercise, and relaxation techniques can also help.
Botox injections cannot cure dystonia, but they can help to relieve symptoms. Botox is a commercially prepared form of botulinum toxin. It is injected directly into the affected muscles. It stops the neurotransmitters that are responsible for muscle spasms from reaching the affected muscles. The effects usually last for 3 months, and then another injection will be necessary.
Clonazepam is an anti-seizure medicine that is sometimes prescribed. However, it has a limited effect, and adverse reactions include mental confusion, sedation, mood swings, and short-term memory loss.
Anticholinergics are a type of medication that treat some types of focal dystonia, and they are effective in some people. Anticholinergics work by blocking the release of a neurotransmitter called acetylcholine. Acetylcholine is known to cause muscle spasms in some cases of dystonia.
It has been suggested that cannabidiol, one of the non-psychoactive cannabinoids found in Cannabis sativa, may reduce dystonic symptoms. However, this has not been confirmed, and scientists call for further studies, especially as cannabis use has been linked to drug abuse and adverse effects.
Dystonia is a lifelong disorder, and very few people experience a remission. Life expectancy is normal, but symptoms persist. This can mean that patients have to limit certain activities.
As patients learn to live with dystonia, physicians can help them to manage symptoms by using pain relief and adapting movement and posture.