Kernig's sign

Physical sign of meningeal irritation in which, with the hip flexed to a 90° angle, passive extension of the knee is limited or produces pain due to reflex hamstring muscle spasm.

Causes

• Meningitis: Bacterial, viral, fungal or tuberculous

• Subarachnoid hemorrhage with meningeal irritation

• Noninfectious meningeal irritation

  • Meningism associated with systemic infections or inflammatory states

  • Chemical meningitis

  • Drug-induced aseptic meningitis

• Other causes

  • Intracranial inflammatory disorders

  • Severe headache syndromes associated with meningeal irritation

  • Spinal inflammatory conditions (rare)