The classic signs of upper motor neurone lesions became recognised in the second half of the 19th century. Charcot and his colleagues first distinguished them from the flaccid weakness of poliomyelitis, posterior column lesions (locomotor ataxy), neuropathic, and myopathic lesions. The contributions of Erb,¹ Marshall Hall,² and Westphal³ to the related tendon reflexes are well know, but the origins of clonus are less clearly portrayed. The import of these signs can hardly be overestimated. In Charcot’s lectures (references as in his text)⁴ he said of clonus:

“. . .known in France under the name of provoked trepidation, or provoked spinal epilepsy. German writers call it the foot-phenomenon (Fussphoenomen) or ankle clonus. But the discovery of this sign belongs to French clinical observers. Since 1863. . .it …