Differential Diagnosis for Passing Out when Flexing Cervical Spine

• Single Most Likely Diagnosis
  • Vasovagal Syncope: This condition is often triggered by specific movements or actions, including flexing the cervical spine, which can stimulate the vagus nerve and lead to a sudden drop in heart rate and blood pressure, resulting in fainting.
• Other Likely Diagnoses
  • Cervical Spondylotic Myelopathy: This condition involves compression of the spinal cord in the neck, which can lead to a variety of symptoms, including dizziness or fainting upon certain movements, due to the compression of blood vessels or the spinal cord itself.
  • Chiari Malformation: A structural defect in the cerebellum that controls balance can cause symptoms such as dizziness or fainting, especially with certain head or neck movements.
• Do Not Miss Diagnoses
  • Vertebral Artery Dissection or Stroke: Although less common, dissection of the vertebral artery can occur with neck movements and lead to stroke or transient ischemic attacks, presenting with symptoms like fainting.
  • Subclavian Steal Syndrome: A condition where there's a significant stenosis or occlusion of the subclavian artery, leading to reversal of blood flow in the vertebral artery, which can cause syncope, especially with arm exercise or certain neck movements.
• Rare Diagnoses
  • Multiple System Atrophy (MSA): A rare neurodegenerative disorder that can cause autonomic dysfunction, leading to orthostatic hypotension and fainting spells, potentially triggered by specific movements.
  • Ehlers-Danlos Syndrome: A group of disorders that affect connective tissues supporting the skin, bones, blood vessels, and many other organs and tissues, which can lead to vascular complications, including fainting due to vascular instability or other mechanisms.