Which sign is associated with multiple sclerosis and involves an electric shock sensation upon neck flexion?

Which sign is associated with multiple sclerosis and involves an electric shock sensation upon neck flexion?

• A. Babinski sign
• B. Lhermitte's sign
• C. Romberg sign
• D. Hoffman's sign

Answer: (B)

Lhermitte's sign reflects demyelination in the cervical spinal cord, which is common in multiple sclerosis. When the neck is flexed, the stretched, demyelinated dorsal column fibers send an electric shock-like sensation that can travel down the spine and into the limbs. This characteristic provocative sign is a classic clue for MS. The other signs point to different neurologic processes but don’t produce the neck flexion–induced electric sensation. Babinski is an upper motor neuron plantar response indicating corticospinal tract involvement but not tied to neck movement. Romberg tests proprioceptive and dorsal column function for balance—unsteadiness with eyes closed—without the specific electric shock in response to neck flexion. Hoffmann sign is a brisk, reflexive finger/finger-thumb response signaling corticospinal tract disease, again not tied to the neck flexion sensation described. So the neck flexion–induced electric shock sensation is characteristic of Lhermitte's sign, strongly associated with MS.

Lhermitte's sign reflects demyelination in the cervical spinal cord, which is common in multiple sclerosis. When the neck is flexed, the stretched, demyelinated dorsal column fibers send an electric shock-like sensation that can travel down the spine and into the limbs. This characteristic provocative sign is a classic clue for MS.

The other signs point to different neurologic processes but don’t produce the neck flexion–induced electric sensation. Babinski is an upper motor neuron plantar response indicating corticospinal tract involvement but not tied to neck movement. Romberg tests proprioceptive and dorsal column function for balance—unsteadiness with eyes closed—without the specific electric shock in response to neck flexion. Hoffmann sign is a brisk, reflexive finger/finger-thumb response signaling corticospinal tract disease, again not tied to the neck flexion sensation described.

So the neck flexion–induced electric shock sensation is characteristic of Lhermitte's sign, strongly associated with MS.