Dystonia is a rare movement disorder, defined by intermittent or sustained involuntary movements and/or postures. The term can refer both to a clinical syndrome and to a group of primary movement disorders in which dystonia represents the predominant manifestation. Adult-onset isolated focal dystonia is the most common form. The aim of this narrative review is to present the current understanding of adult-onset isolated focal dystonia, focusing on its recently revised classification, pathogenesis, and therapeutic approaches. The updated classification system emphasize a two-axis framework integrating clinical features and aetiology, therefore facilitating improved phenotypic characterization and differential diagnosis. The underlying pathophysiological mechanisms of isolated focal dystonia remain incompletely understood, both genetic and environmental factors playing a role. Contemporary models conceptualise dystonia as a network disorder involving the striato–thalamo–cortical and cerebellar circuitry, with evidence supporting impaired inhibitory control, abnormal sensorimotor integration, and maladaptive neuroplasticity. The treatment remains largely symptomatic, with botulinum toxin representing first-line therapy, although its efficacy may be limited in some cases.
Mitrea et al. (Sun,) studied this question.