amyotrophiclateral sclerosis

a·my·o·tro·phic lateral sclerosis (ā'mī-ə-trōʹfĭk, -trŏfʹĭk, ā-mī'-) n. Abbr. ALS

A chronic, progressive disease marked by gradual degeneration of the nerve cells in the central nervous system that control voluntary muscle movement. The disorder causes muscle weakness and atrophy and usually results in death. Also called Lou Gehrig's disease.

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