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outside the pyramidal tracts.
extrapyramidal disease (extrapyramidal syndrome) any of a group of clinical disorders marked by abnormal involuntary movements, alterations in muscle tone, and postural disturbances; the group includes parkinsonism, chorea, athetosis, and others.
extrapyramidal system a functional, rather than anatomical, unit comprising the nuclei and fibers (excluding those of the pyramidal tract) involved in motor activities; they control and coordinate especially the postural, static, supporting, and locomotor mechanisms. It includes the corpus striatum, subthalamic nucleus, substantia nigra, and red nucleus, along with their interconnections with the reticular formation, cerebellum, and cerebrum; some authorities include the cerebellum and vestibular nuclei. Called also extrapyramidal tract.
abnormalities of movement related to injury of motor pathways other than the pyramidal tract.
extrapyramidal syndromeNeurology A condition characterized by a range of findings–eg, rigidity, tremors, drooling, shuffling gait–parkinsonism, akathisia–restlessness, dystonia–odd involuntary postures, akinesia–motor inactivity, and other neurologic disturbances Etiology Extrapyramidal dysfunction, often a reversible side effect of certain psychotropics–eg, phenothiazines. See Simpson-Angus Scale, Tardive dyskinesia.
ex·tra·py·ram·i·dal syn·drome(ekstră-pĭr-ami-dăl sindrōm)
Abnormalities of movement related to injury of motor pathways other than the pyramidal tract.