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botulinum toxin. Abstract: Task-specific dystonias are primary focal dystonias characterized by excessive muscle contractions producing abnormal postures during selective motor activities that frequently involve highly skilled, repetitive movements. Historically these peculiar postures were considered psychogenic but have now been classified as forms of dystonia. Writer’s cramp is the most commonly identified task specific dystonia and has features typical of this group of disorders. Symptoms may begin with lack of dexterity durin