Myoclonic dystonia, a genetic form of dystonia, is characterized by rapid jerking movements alone or in combination with the sustained muscular contractions and postures of dystonia.

Terms used to describe myoclonic dystonia include: myoclonus dystonia, inherited myoclonus-dystonia syndrome, DYT11 dystonia

Note: Some researchers believe myoclonic dystonia is a variation of hereditary essential myoclonus.

Symptoms
 

Myoclonus is a movement dystonia characterized by sudden, brief, shock-like movements. Individuals with myoclonic dystonia exhibit symptoms of dystonia plus very prominent myoclonic movements. The distribution of these rapid "jerks" is variable but most frequently affects the central part of the body, including the shoulders, arms, neck, and trunk. Rarely are the face and legs affected.

Symptoms may be impacted by the consumption of alcohol. Non-movement related features may be present including depression, anxiety, obsessive-compulsive disorder, personality disorders, and panic attacks. The age of onset is in the first or second decade of life, although some cases of adult-onset have been reported. Most frequently, the disorder appears to be slowly progressive for a few years after onset, stabilizes, and then fluctuates slightly over the years or shows a mild spontaneous improvement.

Cause
 

Myoclonic dystonia is often a familial disorder seen in successive generations. Scientists have uncovered that multiple mutations in the epsilon-sarcoglycan gene associated with this form. The function of this gene is still unknown. This disorder is inherited dominantly but only a percentage of individuals who inherit the mutation develop symptoms.

Diagnosis

Diagnosis of myoclonic dystonia is based on family history from the affected individual and the physical and neurological examination.

If the condition presents with both myoclonus and dystonia, it may be classified as "myoclonic dystonia" or "hereditary dystonia with lightning jerks responsive to alcohol."If dystonia is not present or is only a minor component, it may be classified as "hereditary essential myoclonus."

Treatment
 

Medications that may be helpful for the treatment of myoclonic dystonia include benztropine, clonazepam, neuroleptics, dopamine agonists, and perhaps gamma-hydroxybutyrate (GHB).

Complementary therapies may be explored, especially physical therapy, aquatic physical therapy, and regular relaxation practices.

Sources Dystonia medical research foundation