A 28-year-old right-handed woman presents with a 3-month history of progressive involuntary hand posturing that occurs exclusively when she attempts to write. She reports that her fingers curl inward and her wrist flexes, making it impossible to hold a pen normally. The symptoms do not occur during other fine motor tasks such as typing, eating with utensils, or playing the piano. She notes that the dystonia partially resolves when she touches her chin with her affected hand or changes her grip. Neurological examination reveals normal strength, reflexes, and sensory testing. Brain MRI is normal. There is no family history of movement disorders. Which of the following is the most likely diagnosis?

1. A)Primary generalized dystonia
2. B)Task-specific focal dystonia (writer's cramp)GABARITO
3. C)Essential tremor with secondary dystonic features
4. D)Psychogenic movement disorder
5. E)Cervical dystonia with overflow to the hand