Brudzinski Sign

Brudzinski sign is performed with the individual lying flat on their back. The examiner then places one hand behind the individual’s head and the other on their chest to prevent them from rising. A positive Brudzinski sign is considered when neck flexion causes the individual to flex their hips and knees automatically.

The Brudzinski sign is often performed with the Kernig sign. To elicit the Kernig sign, a leg is raised with the knee flexed to a 90-degree angle. Resistance, pain, or inability to extend the knee indicates a positive Kernig sign. 

Bruzdinski sign occurs due to meningeal irritation caused by spinal cord movement or nerves against the meninges. It is thought that passive neck flexion stretches the nerve roots through the inflamed meninges, leading to reflex flexion of hips and knees to relieve the pain. 

Negative Brudzinski and Kernig signs should not rule out meningitis. The Brudzinski and Kernig signs were described over a century ago in individuals with severe, late-stage tuberculous and bacterial meningitis. Several studies have shown low sensitivity to Kernig and Brudzinski signs to detect meningitis. Nonetheless, because of their high specificity, if Kernig or Brudzinski sign is present, meningitis is likely. 

Brudzinski neck sign raises suspicion of meningitis. It can be elicited by flexing the individual’s neck while lying flat on their back. If passive flexion of the neck results in reflex flexion of the hips and knees, it’s a positive sign. A lumbar puncture should be performed if meningitis is suspected.