• The disease
• Diagnosis
• Treatment options

 

Definition

Cervical dystonia (or spasmodic torticollis) is the most common form of focal or localized dystonia. Neurological in origin, it is characterized by muscular spasms that cause abnormal movements of the neck, head and sometimes the shoulders. The neck muscles may contract, twist, tremble, or remain blocked in one direction, giving an awkward and uncomfortable posture.

 

Symptoms and impact on health

The symptoms of spasmodic torticollis generally appear very gradually. The abnormal head posture can be intermittent and may not be uncomfortable. Often, it is noticed only by the person’s friends and family. The disease may also be triggered more suddenly by illness or physical trauma.
It causes:

• contractions of varying duration, causing the head to become locked in an abnormal, awkward posture;
• jerking movements of the head;
• neck pain;
• raised shoulder.

Over time, cervical dystonia causes involuntary twisting of the head, which can take different forms:

• torticollis: head twisted to right or left (in over 70% of cases),
• laterocollis: head tilted towards the shoulder (in 40 to 70% of cases),
• anterocollis: head tilted forward (in 10 to 20 % of cases),
• retrocollis: head tilted back (in 25 to 35 % of cases),
• complex torticollis: a combination of several deviations.

Progression of the disease varies. In 6 to 12.5% of cases, patients experience spontaneous remission that can last from a few months to several years before symptoms return. In the majority of patients, the symptoms get worse during the first five years and then stabilize. For others, there are periods of more intense symptoms and periods of relief. In rare cases, the dystonia can spread to other parts of the body close to the area initially affected.

 

Risk factors

There is still much to discover about the causes of cervical dystonia, which can be primary or secondary. In primary dystonia, there is no identifiable cause of the dystonic symptoms. Secondary dystonia, on the other hand, presents as a result of a specific structural or metabolic problem, usually associated with other neurological disorders. The most common causes of secondary dystonia are physical trauma and reactions to medication.

Spasmodic torticollis may affect only one member (a sporadic case), or several members of the same family, indicating that genetic factors may play a role. However, it has not been possible to determine the proportion of cases concerned.

 

Incidence

Cervical dystonia is the most common form of localized (or focal) dystonia.

In Europe, spasmodic torticollis affects roughly 57 people in a million. Onset is usually around age 40, and the majority of patients develop the condition between the ages of 30 and 60. Earlier onset in childhood or young adulthood can also occur. Cervical dystonia affects slightly more women than men.