spinal muscle atrophy


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Related to spinal muscle atrophy: Werdnig-Hoffman disease

spinal muscle atrophy

Werdnig-Hoffmann disease Neurology A group of conditions that cause progressive muscle degeneration and weakness; SMA is the 2nd most common fatal AR disorder after cystic fibrosis, affecting 1:6000-20,000 newborns/yr–US; SMAs selectively affect the α motor neuron, and are characterized by anterior horn cell degeneration, accompanied by muscle weakness, atrophy, progressive symmetrical limb and trunk paralysis; in type I, the most severe form, infants have weak muscles, feeding and breathing problems, death usually occurs before age 3; other types affect increasingly older Pts
Spinal muscle atrophy–Types
I Acute/infantile onset form of Werdig-Hoffmann
II Intermediate/childhood onset form
III Juvenile onset form of Kugelberg-Welander
IV Adult onset form