How to perform Brudzinski's sign on a patient with suspected meningitis?

How to Perform Brudzinski's Sign

To perform Brudzinski's sign, place the patient supine and passively flex the patient's neck; a positive sign occurs when this maneuver causes involuntary flexion of the patient's hips and knees. 1

Technique

• Position the patient lying flat on their back (supine position) 1
• Place your hand behind the patient's head and gently flex the neck forward, bringing the chin toward the chest 1
• Observe the patient's lower extremities during this maneuver 1
• A positive Brudzinski's sign is present when passive neck flexion causes reflexive flexion of both hips and knees 1

Clinical Context and Limitations

Poor Diagnostic Performance

Brudzinski's sign should not be relied upon for diagnosis of meningitis due to its extremely poor sensitivity. 1 The evidence demonstrates:

• Sensitivity is only 9% in adults, meaning it misses 91% of meningitis cases 1, 2
• In pediatric populations, sensitivity is somewhat better at 66%, but still inadequate to rule out disease 1
• The sign has low diagnostic accuracy for predicting cerebrospinal fluid pleocytosis 1
• Absence of Brudzinski's sign cannot be used to exclude bacterial meningitis 1

Historical Context

Brudzinski actually described several meningeal signs beyond the commonly known "nape of the neck" sign, including contralateral leg signs that are unfamiliar to most clinicians today 3. The original descriptions date to 1909 4.

Clinical Implications

When Meningitis is Suspected

• All patients with suspected meningitis require hospital referral and cerebrospinal fluid examination regardless of whether Brudzinski's sign is present or absent 1
• CSF analysis remains the cornerstone of diagnosis with the highest diagnostic accuracy 2
• The classic triad of fever, neck stiffness, and altered mental status is present in only 41-51% of bacterial meningitis cases 1, 2
• No single clinical sign of bacterial meningitis is present in all patients 1, 2

Alternative Assessment Approach

Rather than relying on Brudzinski's sign, focus on documenting:

• Presence or absence of headache 1
• Altered mental status 1
• Fever 1
• Any rash 1
• Seizures 1
• Signs of shock (hypotension, poor capillary refill) 1

The combination of symptoms and signs is more useful than any individual finding for identifying serious disease, but CSF examination is mandatory when meningitis is suspected. 1