Traumatic Vertebral Artery Injury After Subaxial Cervical Spine Injuries: Incidence, Risk Factors, and Long-Term Outcomes: A Population-Based Cohort Study.

Background and objectives: Vertebral artery injury (VAI) because of traumatic subaxial cervical spine injury is a rare but potentially devastating condition as it could lead to stroke. The aim of this study was to examine the incidence, risk factors, outcomes, and radiographic predictors of VAI in patients surgically treated for subaxial cervical spine injuries at a tertiary care trauma center.

Methods: This is a retrospective population-based cohort study, including all patients surgically treated for traumatic subaxial cervical spine injuries at the study center between 2006 and 2018. Primary outcomes included mortality and morbidity after the injury. Propensity score matching, survival, univariable, and multivariable analyses were used to study the outcomes of interest.

Results: Traumatic VAI primarily occurred after high-energy traumas such as motor vehicle accidents and falls from heights. The median age was 64.4 years (47.4-69.1), and 69% were male. In the cohort of patients with subaxial cervical injury, 54% had a spinal cord injury (SCI). In the subgroup with VAI, the frequency of SCI was 66% and a concomitant SCI and VAI were associated with a more severe American Spinal Cord Injury Association Impairment Scale grade ( P = .015). However, after accounting for age, sex, and associated injuries, VAI did not affect postoperative complications, short- or long-term outcomes, or mortality rates. Facet joint dislocation was a unique radiographic predictor of VAI (odds ratio 3.8 [CI 1.42-10.7], P = .009).

Conclusion: The findings suggest that clinical outcomes of patients with traumatic cervical spine injuries were not negatively affected by the presence of a VAI. Several radiographic factors were associated with VAI; however, only facet joint dislocation remained as an independent predictor of this injury.