Brudzinski’s Sign

Brudzinski’s Sign 🧠

Definition:
Brudzinski’s sign is a clinical sign of meningeal irritation, commonly seen in meningitis.

🔍 How to Elicit the Sign:

Ask the patient to lie supine (on their back).

The examiner flexes the patient’s neck (brings the chin towards the chest).

A positive Brudzinski’s sign occurs when:

The hips and knees automatically flex in response to neck flexion.

⚕️ Mechanism (Why It Happens):

Flexion of the neck stretches the inflamed meninges.

This irritation causes a reflex flexion of the lower limbs to reduce tension on the meninges.

💡 Clinical Significance:

Indicates meningeal irritation, seen in:

Meningitis

Subarachnoid hemorrhage

(Occasionally) severe meningeal inflammation from other causes.

🧩 Associated Signs:

Kernig’s Sign: Pain or resistance when extending the knee while the hip is flexed at 90°, also due to meningeal irritation.

📋 Summary Table:
Feature Brudzinski’s Sign
Position Supine
Action Flex the neck
Positive Response Involuntary flexion of hips & knees
Indicates Meningeal irritation (meningitis, SAH)