A clinical approach to focal dystonias

Abstract

Dystonia is a hyperkinetic movement disorder (HMD), characterised by sustained or intermittent involuntary muscle contractions resulting in abnormal postures and / or movements [1]. Although primary dystonia has an estimated prevalence of 16 per 100,0002, the diagnosis may be delayed, due to its clinical heterogeneity, the lack of objective biomarkers and the potential for pseudodystonic conditions to mimic it [1,3]. We provide an overview of the classification and common subtypes of focal dystonia, focusing on the clinical phenomenology and diagnosis.