Lhermitte's Sign: The Current Status.

Lhermitte's sign was described by Marie and Chatelin and named after Jean Lhermitte. This sign is mostly described as an electric shock like condition by some patients of multiple sclerosis. This sensation occurs when the neck is moved in a wrong way or rather flexed. It can also travel down to the spine, arms, and legs, and sometimes the trunk. Demyelination and hyperexcitability are the main pathophysiological reasons depicted for the Lhermitte's sign. Other causes for Lhermitte's sign include transverse myelitis, behçet's disease, trauma, etc. This article reviews the Lhermitte's sign, its history, and its etiopathophysiology. Very few studies are available on Lermitte's sign and more research need to be done on the same to ensure its sensitivity and specificity.