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Cervical Dystonia
Current Considerations for the Management of Cervical Dystonia
a report by
Bahman Jabbari, MD
Professor of Neurology, Yale University School of Medicine
Cervical dystonia (CD) is a focal dystonia of neck and shoulder muscles that pattern of dystonia is focal and often affects the cervical region. In some
causes neck and shoulder pain, limitation of neck movements, and, patients with DYT1 dystonia, CD may be the most prominent feature. In
sometimes, involuntary head and neck movements. Primary CD is the most younger patients, the work-up should include brain magnetic resonance
common form of adult-onset focal dystonia, with a prevalence of six to nine imaging (MRI), metabolic screening, and—in some patients—genetic testing.
per 100,000 population.
1,2
The peak age at onset is between 40 and 45 In older patients, when there is a suspicion of cervical spine disease one should
years, with females more commonly affected than males (male-to-female obtain MRI of the cervical spine and the cervico–cranial junction.
ratio 1.4:2.2).
3,4
The onset of CD is often insidious, with neck stiffness,
limitation of neck movements, abnormal neck posture, and neck pain. Koukouni et al.
10
reported clinical and genetic characteristics of 76 patients
Misdiagnosis and delayed diagnosis are not uncommon. with CD with age at onset below 28 years (mean 21 years). The male-to-
female ratio was 1.24:1, and there was a family history of dystonia or tremor
Primary CD has two main clinical forms. The first is characterized by in 26%. Neck trauma or surgery was present in 17% of the patients. One-
abnormal posture of the head and neck, limitation of head movements, and third developed dystonia in the contiguous parts of the body. Another
hypertrophy of overactive muscles, but no involuntary head movements. The one-third experienced partial remission, but dystonia relapsed within five
abnormal posture can be purely rotational (torticollis), head tilt (laterocollis), years. The DYT1 gene mutation was negative in all 15 patients who were
head retroflexion (retrocollis), or anteflexion (antecollis), or a combination. tested for it. This young-onset CD seems to be distinct from the more
Torticollis is the most common among single deviations, while torticollis plus common late-onset form of CD in terms of male predominance, higher
laterocollis is the most common of the combined forms. The second form is incidence of family involvement, and more transient remissions.
characterized by the features of the first type plus involuntary head jerks
(myoclonic dystonia). The head jerks are often exaggerated when the patient Primary CD is probably a genetic disorder, but the precise genetic alteration
attempts to move the head toward the direction of movement limitation, needs to be elucidated. In one German kindred with DYT7 mutation, CD
and are sometimes seen exclusively at the end of the attempted rotation. In was the prominent dystonic feature.
11
In a recent study, the investigators
some patients, head movements are oscillatory (dystonic tremor) and difficult showed that the presence of the D216H variant of the DYT1 gene in the
to differentiate from the cervical form of essential tremor. Remission occurs absence of the DYT1 mutation increases the risk for developing CD even in
in 10–20% of patients, but is generally transient and usually does not last patients without a family history of CD.
12
beyond one year.
5,6
Approximately 10% of patients disclose a history of CD
in first-degree relatives, and 26–52% describe tremor or dystonia in family Medical Treatment
members.
6
CD is distinct from other forms of late-onset dystonia because of The most commonly used pharmacological agents for the treatment of
pain, which is often described as ‘aching’ or ‘pulling’ and occurs in 70–75% CD are anticholinergic drugs (in particular trihexyphenydil), baclofen, and
of patients.
7,8
In one study the following distribution was reported: neck, clonazapam. Greene et al.
13
reported the following order of effectiveness for
100%; shoulder, 73%; back, 46%; and arm, 15%. The maximum pain is these agents in CD: trihexyphenydil 50%, baclofen 21%, and clonazepam
usually felt in the muscles ipsilateral to the side of the chin deviation. Patients 11%. Unfortunately, high doses of anticholinergics (20–80mg/day for
learn to perform sensory tricks (geste antagoniste) to improve head posture trihexyphenidyl) may be needed to improve symptoms of CD, and such
and decrease neck pain. The most common maneuver is touching the chin
on the side of ipsilateral head rotation or tilt. However, pressing the head
Bahman Jabbari, MD, is a Professor of Neurology and Director of
back against a high chair and holding the occipital region between the Parkinson’s Disease and Movement Disorder Program at Yale
interlocked fingers may also work. Sensory tricks usually lose some of their
University School of Medicine. His previous appointments
include Director of the Epilepsy and Movement Disorder
effectiveness with the passage of time.
Programs at Walter Reed Army Medical Center, Washington DC,
and Chairman of the Neurology Department at the Uniformed
Differential diagnosis of late-onset CD includes a number of secondary causes.
Services University at Bethesda, Maryland. Professor Jabbari is a
Fellow of the American Academy of Neurology (AAN) and a
Dystonic posture of the neck may arise from cervical spine disease or disorders
member of the International Movement Disorder Society (IMDS),
of the cervico–cranial junction. CD can occur after head or neck injury, and the American Neurological Association (ANA), and the American
dystonic posture of the neck may be seen during the course of a number of
Academy of Clinical Neurophysiology (AACN).
neurodegenerative disorders such as Parkinson’s disease, Parkinson plus
E:
bahman.jabbari@yale.edu
syndromes, and Wilson’s disease. In the DYT7 form of genetic dystonia the
© TOUCH BRIEFINGS 2008
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