Kernig sign is elicited by what finding?

• A. Brudzinski Sign
• B. Kernig Sign
• C. NEXUS Criteria
• D. Babinski Sign

Answer: (B)

Kernig sign signals meningeal irritation. To test it, with the patient lying on their back, you flex the hip and knee to 90 degrees and then try to straighten the knee. A positive finding is pain and resistance to knee extension (often felt in the hamstrings) when the hip is held flexed, sometimes preventing full straightening. This occurs because inflamed meninges and nerve roots are stretched during extension.

Brudzinski sign involves neck flexion causing involuntary flexion of the hips and knees, NEXUS criteria are used to clear the cervical spine in trauma, and Babinski sign is a plantar reflex abnormality. The Kernig maneuver specifically targets meningeal irritation by the dynamics of hip flexion with knee extension.