Dystonia is a movement disorder characterized by sustained muscle contractions, repetitive twisting movements, and abnormal posturing of the trunk, neck, face, or arms and legs (1)
There is impairment of muscle tone resulting in an abnormal posture with excessive contraction of antagonist muscles. A limb is usually held in an extreme of flexion or extension. Facial muscles and the tongue may be involved.
It is often a very isolated, focal condition - for example the hand in writer's cramp. Alternatively, it may be more generalised, as occurs in idiopathic torsion dystonia, or segmental. Dystonia may be a complication of neuroleptic use.
Dystonia can be treated conservatively or surgically:
- currently available conservative management options for dystonia improve the symptoms but do not cure the underlying neurological disorder. The severity of dystonia may progress over time as part of the underlying neurological condition
- surgical options include thalamotomy and pallidotomy; however, benefits may not be maintained in the long term (2)
brain stimulation is another treatment option
- the safety and efficacy of deep brain stimulation for tremor and dystonia (excluding Parkinson?s disease) appears adequate to support the use of this procedure (2)
Dystonia is often confused with spasticity or rigidity and sometimes mistakenly attributed to psychogenic causes. Sometimes the diagnosis is missed and patients often consult several physicians before the correct diagnosis is made (1)
- Tarsy D and Simon DK, Dystonia, N Engl J Med 2006 ; 355:818, Review Article
- NICE (August 2006).Deep brain stimulation for tremor and dystonia (excluding Parkinson?s disease).