What is spinal muscular atrophy?

Also known as: SMA, Werdnig-Hoffman Syndrome, Kugelberg-Welander Syndrome, infantile onset SMA, chronic SMA, mild SMA

Spinal muscular atrophy is a rare degenerative disorder in which the nerve cells in the upper and lower parts of the spinal cord don’t function normally, resulting in muscle wasting and weakness. There are 4 types of SMA (Types I, II, III, and IV) based on symptoms and age of onset.


Reviewed by: Jack Wolfsdorf, MD, FAAP

This page was last updated on: 1/29/2019 3:21:13 PM

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