The Vulnerable Conduit: Uncovering Segment-Specific Pathological Susceptibility and Bony Co-dependence of the Vertebral Artery in a South Indian Cohort

Background The vertebral artery is a vital contributor to posterior cerebral circulation and demonstrates considerable anatomical variability due to its complex embryological development and close relationship with the cervical vertebrae. These variations have important clinical implications during cervical spine surgery, endovascular procedures, and in the assessment of vertebrobasilar insufficiency. However, comprehensive population-specific data on vertebral artery morphology in South Indians remain limited. The present study aimed to evaluate the anatomical variations, morphometric characteristics, and pathological associations of the vertebral artery using three-dimensional computed tomography angiography (3D-CTA) in a South Indian cohort, with special emphasis on segment-specific vulnerability and its relationship with the foramen transversarium. Methodology This retrospective observational study included CTA images of 151 adult patients (100 males and 51 females) obtained between December 2024 and March 2025. Three-dimensional volume-rendered and multiplanar reconstructed images were analyzed to assess vertebral artery origin, level of entry into the foramen transversarium, segment-wise diameter (V1-V4), vertebral artery hypoplasia (≤2 mm), foramen transversarium dimensions, and associated pathological changes. Measurements were independently reviewed by two radiologists. Statistical analysis was performed using SPSS version 19.0 (IBM Corp., Armonk, NA, USA), and a p-value