The clinical expression of primarydystonia

Abstract. Dystonia (from the Greek, altered muscle tone) refers tosustained and vigorous contractions forcing a body region intoan abnormal position that is consistently present. Dystonicpostures and movements can variably combine to produce a widespectrum of clinical presentations. The movement can affect one,two or more body regions, as in focal, segmental or generaliseddystonia. Dystonia arising in childhood tends to progress to ageneralised form; adult-onset dystonia, instead, is often focalor segmental. Dystonic movements have specific features that canbe recognised by clinical observation, such as speed,consistency, predictability, variability and relationship withvoluntary movement. Sensory tricks and gestes antagonistes are manoeuvres thatspecifically alleviate dystonic movements and postures therebyproviding diagnostic clues. The diagnosis of primary dystoniarequires the observation of a consistent clinicalpicture.