Figure 2.

Proposed classification system for ALS.

Notes: The classification system begins at the left of the figure and proceeds through each block toward the right, as noted by the arrow, providing a “picture” of the individual with ALS. Reprinted from The Lancet Neurology; 15(11); Al-Chalabi A, Hardiman O, Kiernan MC, Chi.A, Rix-Brooks B, van den Berg LH. Amyotrophic lateral sclerosis: moving towards a new classification system; 1182–1194; Copyright © 2016 Elsevier Ltd; with permission from Elsevier.¹¹

Abbreviations: ALS, amyotrophic lateral sclerosis; FTD, frontotemporal dementia; LMN, lower motor neuron; PLS, primary lateral sclerosis; PMA, progressive muscle atrophy; UMN, upper motor neuron.