spinal muscular atrophy(redirected from Infantile spinal muscular atrophy)
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spinal muscular atrophy
Any of several forms of a hereditary, progressive disease that involves loss of motor neurons in the spinal cord and brainstem and is characterized by muscle weakness and atrophy that vary in severity and age of onset.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.