Phenomenology and classification of dystonia: A consensus update

Abstract

This report describes the consensus outcome of an international panel consisting of investigators with years of experience in this field that reviewed the definition and classification of dystonia. Agreement was obtained based on a consensus development methodology during three in-person meetings and manuscript review by mail. Dystonia is defined as a movement disorder characterized by sustained or intermittent muscle contractions causing abnormal, often repetitive, movements, postures, or both. Dystonic movements are typically patterned and twisting, and may be tremulous. Dystonia is often initiated or worsened by voluntary action and associated with overflow muscle activation. Dystonia is classified along two axes: clinical characteristics, including age at onset, body distribution, temporal pattern and associated features (additional movement disorders or neurological features), and etiology, which includes nervous system pathology and inheritance. The clinical characteristics fall into several specific dystonia syndromes that help to guide diagnosis and treatment. We provide here a new general definition of dystonia and propose a new classification. We encourage clinicians and researchers to use these innovative definition and classification and test them in the clinical setting on a variety of patients with dystonia.

Deep Brain Stimulation for Movement Disorders of Basal Ganglia Origin: Restoring Function or Functionality?

“…Dystonia is often initiated or worsened by voluntary action and associated with overflow muscle activation^ [180]. Co-contraction of agonist and antagonist muscles is common.…”

Nonmotor symptoms in primary adult‐onset cervical dystonia and blepharospasm

“…Dystonic movements are typically patterned, twisting, and may be tremulous. Dystonia is often initiated or worsened by voluntary action and associated with overflow muscle activation (Albanese et al., 2013). According to the involvement of body region, dystonia can be classified into focal, segmental, multifocal, hemidystonia, and generalized dystonia (Albanese et al., 2013).…”

“…Dystonia is often initiated or worsened by voluntary action and associated with overflow muscle activation (Albanese et al., 2013). According to the involvement of body region, dystonia can be classified into focal, segmental, multifocal, hemidystonia, and generalized dystonia (Albanese et al., 2013). Cervical dystonia (CD) and blepharospasm (BSP) are the most common forms of focal dystonia, with a prevalence of 4.98 per 100 000 and 4.24 per 100 000 separately (Steeves, Day, Dykeman, Jette, & Pringsheim, 2012).…”

Classification of dystonia in childhood

“…A combination of the descriptors on the two set of axis was considered to "provide meaningful information on any dystonia patient and serve as a basis for the development of research and treatment strategies". This revised classification has potential benefits over those previously proposed, not least of which being the move away from the overly reductive division into "primary" and "secondary" dystonia, with the M A N U S C R I P T A C C E P T E D ACCEPTED MANUSCRIPT attendant difficulties these terms have posed [6]. One potential benefit is also to facilitate syndromic associations, aiding recognition of distinct disease entities, ultimately aiding diagnosis.…”