Vertebral artery dissection after neck extension in an adult patient with Klippel–Feil syndrome

The association between Klippel–Feil syndrome and vertebral artery dissection is quite rare. We report an adult patient with vertebral artery dissection and Klippel–Feil syndrome, to our knowledge only the third reported case of its kind. A 45-year-old woman with a known history of Klippel–Feil syndrome presented with occipital head and neck pain following forced neck extension. Diagnostic cerebral angiography revealed a high grade vertebral artery stenosis, consistent with vertebral artery dissection. Following 6 months of medical management, a repeat diagnostic angiogram revealed complete healing of the vessel. While cervical fusion, as seen in Klippel–Feil syndrome, has previously been shown to cause neurologic injury secondary to hypermobility, the association with vertebral artery dissection is incredibly rare. We hypothesize that this hypermobility places abnormal shear force on the vessel, causing intimal injury and dissection. Patients with seemingly spontaneous vertebral artery dissection may benefit from cervical spine radiography, and this predisposition to cerebrovascular injury strongly suggests further evaluation of vascular injury following trauma in patients with Klippel–Feil syndrome or other cervical fusion as clinically warranted.