Signs with a high positive predictive value* for motor neurone disease where there is a history of progressive motor-only weakness
| Sign | Notes |
|---|---|
| Fasciculations | If generalised (easily missed over the anterior shoulders) |
| Bilateral wasting of the tongue | Lateral borders, particularly where there are also fasciculations (best observed without protrusion) and a brisk jaw jerk or orbicularis oris reflexes |
| The ‘split hand’73 | Preferential wasting of the lateral border of the hand, that is, first dorsal interosseous and abductor pollicis brevis. This is thought possibly to reflect cortical organisation |
| Head drop | Weakness of neck extensors. Myasthenia gravis is a consideration but this sign should not be attributed to cervical spondylosis |
| Emotionality | Exaggerated response to emotional stimuli, usually crying, typically with bulbar weakness and often with an abnormal response to glabellar tap |
| Cognitive or behavioural impairment | Frontotemporal dementia overlap features |
*Not formally validated.