Lhermitte's Sign: Screening for Spinal Cord Pathology

Lhermitte's Sign is a neurological test used to identify irritation of the spinal cord (myelopathy). It is classically associated with conditions like Multiple Sclerosis (MS) and cervical stenosis.

[Image of Lhermitte's sign test]

1. Purpose

The primary purpose of Lhermitte's Sign (or Lhermitte's Phenomenon) is to **screen for** spinal cord pathology, specifically dysfunction of the dorsal columns. It is commonly associated with Multiple Sclerosis (MS), cervical spondylotic myelopathy, or disc herniation compressing the cord.

2. How to Perform

1. The patient is typically positioned in long sitting (legs straight out) on the examination table.
2. The examiner instructs the patient to relax their neck.
3. The examiner passively and slowly flexes the patient's head forward, bringing the chin towards the chest.
4. The examiner asks the patient what they feel during this movement.

3. Positive & Negative Sign

Positive Sign (Test is POSITIVE):
A positive test is the presence of:

• A sudden sensation of an "electric shock" moving down the spine and into the upper or lower limbs.
• This indicates dural irritation or spinal cord compression (myelopathy).

Negative Sign (Test is NEGATIVE):
A negative test is when no electric shock sensation is produced. (Local neck pain or stiffness does not count as a positive sign for Lhermitte's).