Classifying vertebral artery anatomy abnormality in children with skeletal dysplasia.

Purpose Skeletal dysplasia (SKD) have predictably abnormal occipitocervical skeletal anatomy, but a similar understanding of their vertebral artery anatomy is not known. Knowledge and classification of vertebral artery anatomy in SKD patients is important for safe surgical planning. We aimed to determine if predictably abnormal vertebral artery anatomy exists in pediatric SKD. Methods We performed a retrospective review of CTAs of the neck for pediatric patients at a single institution from 2006 to 2018. CTAs in SKD and controls were reviewed independently in blinded fashion by two radiologists who classified dominance, vessel curvature at C2, direction at C3, and presence of fenestration and intersegmental artery. Results 14 skeletal dysplasia patients were compared to 32 controls. The path of the vertebral artery at C2 foramen was no different between the cohorts or by side, right (p = 0.43) or left (p = 0.13), nor for medial or lateral exiting direction from C3 foramen on right (p = 0.82) or left (p = 0.60). Dominance was most commonly neutral in both groups (71% in SKD and 63% in controls). There were no fenestrated nor first intersegmental arteries in our cohort. Conclusion No systematic differences were detected between SKD and control patients with respect to vertebral artery anatomy. Nonetheless, surgically relevant variability was observed in both groups. Paying particular attention to the direction of exit at C3 and curvature at C2 with respect to the foramen and vessel dominance are important and easily classifiable abnormalities that both surgeons and radiologists can use to communicate and employ in pre-operative planning. Level of evidence III.