Abnormal findings in nuchal rigidity, Brudzinski sign, or Kernig sign may indicate which conditions?

• A. Meningitis or subarachnoid hemorrhage
• B. Brain tumor
• C. Migraine
• D. Peripheral neuropathy

Answer: (A)

These signs reflect irritation of the coverings of the brain and spinal cord (the meninges). When the meninges are inflamed or irritated, as in meningitis, or when blood is present in the subarachnoid space (subarachnoid hemorrhage), the neck and back can become stiff and movement triggers characteristic reactions. Nuchal rigidity means a stiff neck and limited ability to bend the neck forward. Brudzinski sign appears when passive neck flexion leads to involuntary lifting of the hips and knees. Kernig sign is observed when attempting to straighten a flexed knee at the hip; there is pain or resistance in the back or hamstrings. Taken together, these findings point to meningeal irritation, most classically due to meningitis or subarachnoid hemorrhage.

Other conditions listed don’t typically produce meningeal irritation signs. A brain tumor can cause headache and focal neurologic deficits but not the classic meningeal signs as a primary feature. Migraine is a vascular phenomenon with throbbing headache and usually doesn’t involve stiff neck or positive meningeal signs. Peripheral neuropathy affects peripheral nerves and neuropathic symptoms rather than the meninges, so these signs are not expected.