Anomalous vertebral and posterior communicating arteries as a risk factor in instrumentation of the posterior cervical spine

Bone Joint J. 2014 Apr;96-B(4):535-40. doi: 10.1302/0301-620X.96B4.33210.


We investigated the incidence of anomalies in the vertebral arteries and Circle of Willis with three-dimensional CT angiography in 55 consecutive patients who had undergone an instrumented posterior fusion of the cervical spine. We recorded any peri-operative and post-operative complications. The frequency of congenital anomalies was 30.9%, abnormal vertebral artery blood flow was 58.2% and vertebral artery dominance 40%. The posterior communicating artery was occluded on one side in 41.8% of patients and bilaterally in 38.2%. Variations in the vertebral arteries and Circle of Willis were not significantly related to the presence or absence of posterior communicating arteries. Importantly, 18.2% of patients showed characteristic variations in the Circle of Willis with unilateral vertebral artery stenosis or a dominant vertebral artery, indicating that injury may cause lethal complications. One patient had post-operative cerebellar symptoms due to intra-operative injury of the vertebral artery, and one underwent a different surgical procedure because of insufficient collateral circulation. Pre-operative assessment of the vertebral arteries and Circle of Willis is essential if a posterior spinal fusion with instrumentation is to be carried out safely.

Keywords: Algorithm; Cervical instrumentation surgery; Posterior communicating artery; Risk factor; Three-dimensional CT angiography; Vertebral artery.

MeSH terms

  • Abnormalities, Multiple / surgery
  • Adolescent
  • Adult
  • Aged
  • Aged, 80 and over
  • Atlanto-Axial Joint / abnormalities
  • Cervical Vertebrae / abnormalities
  • Cervical Vertebrae / surgery*
  • Circle of Willis / abnormalities*
  • Circle of Willis / diagnostic imaging
  • Collateral Circulation / physiology
  • Female
  • Humans
  • Joint Instability / diagnostic imaging
  • Joint Instability / surgery
  • Male
  • Middle Aged
  • Preoperative Care / methods
  • Risk Factors
  • Spinal Fusion / adverse effects*
  • Spinal Fusion / instrumentation
  • Tomography, X-Ray Computed
  • Vertebral Artery / abnormalities*
  • Vertebral Artery / diagnostic imaging
  • Vertebral Artery / injuries
  • Vertebrobasilar Insufficiency / complications
  • Young Adult