Primary Torsion Dystonia Clinical Presentation

The following history should be elicited:

• Age of onset
• Initial site of involvement and progression to other body sites and time course of progression
• Occurrence of dystonia at rest, with any specific voluntary action, or posture maintenance
• Presence or absence of tremor or other movement disorders
• Presence or absence of a sensory trick, or geste antagoniste
• A family history of similar symptoms or other involuntary movements, the age of onset of similar symptoms, and body part predominantly affected
• Imaging or laboratory abnormalities (ie, MRI findings, serum ceruloplasmin concentrations) that suggest another cause of dystonia
• Previous therapeutic trial and response to low-dose levodopa, to exclude dopamine-responsive dystonia
• Any secondary etiologies, such as trauma, infectious process, birth injury, or developmental delay
• Use of any medications reported to cause dystonia, such as levodopa, dopamine agonists, antipsychotics, neuroleptics, dopamine-blocking agents, metoclopramide, fenfluramine, flecainide, ergot agents, anticonvulsive agents, and certain calcium channel blockers
• Other neurologic complaints associated with the dystonic symptoms
• Pain, which is not usually a prominent feature except in some cases of cervical dystonia and other forms of secondary dystonia (eg, reflex sympathetic dystrophy and foot dystonia occurring with Parkinson disease)
• Aggravating or attenuating factors
• Degree of functional impairment resulting from the dystonia
• Medication trials, benefits, and adverse effects
• Additional questions about the following may help in determining if dystonia is affecting other body parts (such involvement might not be otherwise volunteered):

  • Increased blinking
  • Intermittent puckering of the mouth
  • Chewing movements
  • Tongue popping
  • Stuttering
  • Difficulty speaking
  • Becoming breathless when speaking with a soft voice
  • Turning, tilting, or shifting of the head in any direction
  • Jerking of the head
  • Twisting of the body
  • Tremors of the hands or feet, arms, or legs
  • Twisting or moving involuntarily when using hands or walking
  • Difficulty with writing
  • History of clumsiness
  • Cramps when using the hands or legs
  • Toes going up or down involuntarily or being pigeon toed

It is important to note the distribution of body parts affected. Although classification of the distribution is arbitrary, it may serve as a useful guide in clinical practice and may help in grouping families and patients for clinical trials and genetic studies.

• Distributions are classified as follows:

  • Focal (single body region)
  • Segmental (contiguous regions)
  • Multifocal (noncontiguous regions)
  • Hemidystonia (a type of multifocal distribution involving an ipsilateral arm and leg)
  • Generalized (leg, trunk, and 1 other region or both legs with or without trunk involvement plus 1 other region)
• The central features that distinguish dystonia from other involuntary movement disorders are the posture-assuming features or directional quality and patterned predictable involvement of a specific set of muscles involved.
• Although the pattern of muscle contractions in dystonia is consistent and predictable, involuntary movements vary with changing postures or tasks.
• The site of involvement may remain focal or progress to involve other parts of the body over time.
• The speed of dystonic contractions may be rapid or slow.
• Various sensory tricks may be performed that diminish the dystonic movements, termed geste antagoniste.
• Dystonic movements intensify with voluntary action. Movements of primary dystonia commonly occur with specific actions and are not present at rest. As the dystonic condition progresses, relatively nonspecific voluntary actions can bring out the dystonic movements. With still further worsening, the affected limb can develop dystonic movements while at rest, and the patient eventually develops sustained posturing.
• Irregular, rhythmic contractions termed dystonia tremors may be observed. The tremor is less regular than essential tremor.
• Facial muscles are affected, as manifested by patterned and sustained contractions of the forehead, eyelids, and lower face. Limbs may be affected as well, and specific voluntary tasks may intensify such contractions. Examples are writing when the upper extremities are affected and walking forward but not backward when lower extremities are affected.
• It is important to note other physical and abnormal neurologic findings in addition to the dystonia.

Dystonia has historically been classified into 2 main etiologic groups: idiopathic (primary) and symptomatic (secondary).^[1] Idiopathic dystonia was distinguished from the symptomatic dystonias both by its lack of known cause and the absence of consistent brain pathology. However, it has become clearer that idiopathic dystonia consists of a group of clinical syndromes that are likely to have a genetic basis. Primary dystonia is a genetically heterogeneous disease.^{[14, 15]} Currently, 17 inherited forms of primary dystonia are recognized: 12 are inherited as autosomal dominant, 4 as autosomal recessive, and 1 (dystonia parkinsonism) as an X-linked recessive trait.^[16]

Table 2 below summarizes the clinical characteristics of primary torsion dystonia associated with different genes. Table 3 below lists the genetic loci for dystonia.

Table 2. Clinical Characteristics of Primary Torsion Dystonia Associated With Different Genes (Open Table in a new window)

Table 3. Genetic Loci for Dystonia (Open Table in a new window)

• Primary dystonia

  • Idiopathic or primary torsion dystonia: Despite a negative family history, a genetic basis for dystonia is not ruled out completely, as its mode of inheritance is usually autosomal dominant with reduced penetrance.
  • Sporadic and familial torsion dystonia
  • Inherited (ie, hereditary) dystonia
• Secondary dystonia

  • Vascular
    • Cerebrovascular, or ischemic injury
    • Arteriovenous malformation
    • Perinatal cerebral injury
  • Infectious
    • Viral encephalitis
    • Subacute sclerosing panencephalitis
    • AIDS
    • Creutzfeldt-Jakob disease
  • Trauma
    • Head trauma
    • Peripheral trauma
  • Brain tumor
  • Toxins - Manganese, carbon monoxide, carbon disulfide, methanol, disulfiram, wasp sting
• Drugs - Levodopa, dopamine agonists, antipsychotics, metoclopramide, fenfluramine, flecainide, ergot agents, anticonvulsant agents, certain calcium channel blockers
• Metabolic conditions

  • Kernicterus
  • Wilson disease
  • Amino acid disorders
  • Glutaric acidemia
  • Methylmalonic acidemia
  • Homocystinuria
  • Hartnup disease
  • Tyrosinosis
  • Lipid disorders
  • Metachromatic leukodystrophy
  • Neuronal ceroid lipofuscinosis
  • Dystonic lipidoses - Niemann-Pick disease, type C (ie, sea blue histiocytosis)
  • Primary antiphospholipid antibody syndrome
  • Gangliosidoses (ie, GM1, GM2)
  • Mitochondrial encephalopathies (eg, Leigh disease, Leber disease)
  • Lesch-Nyhan syndrome
  • Triosephosphate isomerase deficiency^[25]
  • Vitamin E deficiency
  • Biopterin deficiency
• Genetic factors

  • Dystonia plus syndromes
  • Myoclonus dystonia
  • Dopa-responsive dystonia (DRD)
  • Rapid-onset dystonia parkinsonism
  • Lubag or X-linked dystonia parkinsonism
• Neurodegenerative conditions

  • Progressive supranuclear palsy
  • Multiple systems atrophy
  • Corticobasal-ganglionic degeneration
  • Hallervorden-Spatz disease
  • Hypobetalipoproteinemia, acanthocytosis, retinitis pigmentosa, pallidal degeneration (HARP) syndrome
  • Neuroacanthocytosis
  • Spinocerebellar ataxia (SCA), types 1, 2, or 3
  • Ataxia telangiectasia
  • Huntington disease
  • Dentatorubropalidoluysian atrophy
• Demyelination -Multiple sclerosis
• Structural conditions

  • Atlantoaxial subluxation
  • Syringomyelia
  • Arnold-Chiari malformation
  • Congenital Klippel-Feil syndrome