Complex Atlantoaxial Dislocation with Basilar Invagination and an Anomalous Dominant Right Vertebral Artery: C1 Lateral Mass Screw Placement Above the Vertebral Artery
Abstract: Complex atlantoaxial dislocation (AAD) with basilar invagination (BI) is a craniovertebral junction anomaly that can cause progressive myelopathy, and anomalous vertebral artery (VA) anatomy makes C1-C2 instrumentation hazardous. We report an 18-year-old male with quadriparesis for 2 years, with loss of fine touch and joint position sense, and no history of trauma. Imaging showed complex AAD with BI, atlanto-occipital assimilation, a rotated C1-C2 joint, C2-C3 block vertebra, chronic cervical cord injury at C1 and a dominant, abnormally coursing right VA. Posterior fixation was done with a C2 pedicle screw and a right C1 screw placed above the vertebral artery. There was no blood loss, the post-operative course was uneventful and the post-operative X-ray was satisfactory. Careful pre-operative assessment of VA anatomy allows safe, individualised C1 screw placement.
Keywords: Atlantoaxial dislocation; Basilar invagination; Vertebral artery anomaly; C1 lateral mass screw; Craniovertebral junction
How to Cite?: Saddam Singh, Sotin P, Nikhil Bhatt, Aditya Shrivastava, "Complex Atlantoaxial Dislocation with Basilar Invagination and an Anomalous Dominant Right Vertebral Artery: C1 Lateral Mass Screw Placement Above the Vertebral Artery", Volume 15 Issue 10, October 2026, International Journal of Science and Research (IJSR), Pages: 1678-1680, https://www.ijsr.net/getabstract.php?paperid=MR261024221719, DOI: https://dx.doi.org/10.21275/MR261024221719