The diagnosis of ALS requires: | Â |
1 Evidence of LMN degeneration by clinical, electrophysiological or neuropathological examination; | Â |
2 Evidence of UMN degeneration by clinical examination, and | Â |
3 Progressive spread of symptoms or signs within a region or to other regions, as determined by history or examination, | Â |
Together with the absence of: | Â |
[1] Electrophysiological and pathological evidence of other disease that might explain the signs of LMN and/or UMN degeneration, and | Â |
[2] Neuroimaging evidence of other disease processes that might explain the observed clinical and electrophysiological signs | Â |
Categories of clinical diagnostic certainty on clinical criteria alone | Â |
Definite ALS | Â |
• UMN signs and LMN signs in 3 regions Probable ALS |  |
• UMN signs and LMN signs in 2 regions with at least some UMN signs rostral to LMN signs |  |
Probable ALS – Laboratory supported |  |
• UMN signs in 1 or more regions and LMN signs defined by EMG in at least 2 regions |  |
Possible ALS | Â |
• UMN signs and LMN signs in 1 region (together), or |  |
• UMN signs in 2 or more regions |  |
• UMN and LMN signs in 2 regions with no UMN signs rostral to LMN signs |  |