Brudzinksi’s sign, is one of the physically demonstrable symptoms of meningitis, which is an acute inflammation of the membranes that cover the brain and spinal cord as a source of protection, known collectively as the meninges. One of the key symptoms of meningitis is neck stiffness. Severe neck stiffness (nuchal rigidity) causes a patient’s hips and knees to flex when the neck is flexed. It is found in patients with meningitis, subarachnoid hemorrhage and possibly encephalitis.
Another useful physical test for diagnosing meningitis is called Kernig’s sign.
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