Amyotrophic lateral sclerosis (ALS) is uncommon. It usually begins in middle age and proceeds to death in several years. There is loss of anterior horn cells, so that patients present with progressive weakness that proceeds to paralysis from neurogenic muscular atrophy. Because of the loss of anterior horn cells, the anterior (ventral) spinal motor nerve roots with ALS demonstrate atrophy, as seen here in comparison with a normal spinal cord motor nerve roots.