These 3 neurological presentation fall under a larger group known as hyperkinectic disorders that included others type of presentation such as dystonia, myoclonus, tics and tremor. However, this article only focus on differentiation among these 3 as they appeared almost similar. If you were to search for their descriptive manifestation, you will find various description and terminology is being used. This article has no difference, but will preferred a more systematically approach in describing them. Let’s begin shall we?
In describing an abnormal movement, its better to include these:
1. Speed (slow or rapid?)
2. Involuntary or voluntary ?
3. Stereotypical or non-stereotypical / Rhythmic or non-rhythmic / predictable or non-predictable [may use either one]
4. Purposeful, non-purposeful or semi-purposeful
4. Others specific style (writhing, dance-like, ect.)
5. Involvement of muscle group (e.g distal or proximal?)
The author prefered describing these movement in that order. Hence,
A chorea is a rapid, involuntary, non-stereotypical, semi-purposeful (some reference uses non-purposeful), dance-like movements that involved the distal muscle group more than proximal.
An athetosis is a slow, involuntary, non-stereotypical, non-purposeful, writing movements, with a propensity to affects the upper limbs.
Ballismus is a rapid, involuntary, non-stereotypical, non-purposeful, relatively more violent flinging movement, that involved the proximal muscle group more than distal.
Some reference has used the term “repetitive” to further describe the abnormal movement. You may use, but would add up the burden in describing the movement. Sometimes, athetosis is combined with chorea, resulting in choreoathetosis, used to describe a movement presented with combination of both characteristic.
Chorea is typically represented by Syndeham’s chorea and Huntington’s disease. While, ballismus is usually caused by structural lesions of the contralateral basal ganglia and subthalamic nucleus. Athetosis and choreoathetosis are frequently found in child with cerebral palsy.
1. Stephen L. Hausser. Ed. Harrison’s neurology in clinical medicine. 2nd edition. McGraw Hill. New York, NY. 2010
2. A.J. Larner. Ed. A dictionary of neurological signs. 3rd ed. Springer. New York, NY. 2011.
3. Helms A, Shulman L. Chorea, Athetosis, and Ballismus. In: Kaplan PW, Fisher RS, editors. Imitators of Epilepsy. 2nd edition. New York: Demos Medical Publishing; 2005. Available from: http://www.ncbi.nlm.nih.gov/books/NBK7479/
4. Terence D. Sanger et al. Definition and classification of hyperkinetic movements in childhood. Movement Disorders.
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