One sided body dystonia

Other names: Hemidystonia

Type: Affects one side of the body

Hemidystonia is a neurological movement disorder characterised by continuous or intermittent muscle contractions which cause abnormal, often painful, repetitive movements in one side of the body, usually the arm and leg and/or face.

Hemidystonia can either be:

• acquired (secondary) – a dystonia that appears to have a specific cause such as drug reaction, brain injury, or as a symptom of another neurological or metabolic disorder or;
• idiopathic – a dystonia with no known or clear cause

In acquired hemidystonia the first symptoms are frequently a sudden onset of weakness on one side of the body. Dystonia may then appear as the weakness recovers – but the dystonia does not tend to spread after this. The dystonia may appear immediately after the brain damage or weeks, months or even years later and there is often a significant delay in cases of perinatal and head injury.

Idiopathic hemidystonia may spread more slowly. Symptoms may spread through the affected side during the first few months to years, followed by an eventual plateau and stabilisation.

Hemidystonia should be diagnosed and treated by a neurologist specialising in movement disorders.