Congenital hypoplasia of the right C6 pedicle and anomalous vertebral artery entry: illustrative case.

Background: Congenital anomalies of the cervical spine are rare, often asymptomatic conditions that may only be detected incidentally. However, they can have significant clinical implications, particularly when associated with vascular anomalies. This case highlights a unique combination of congenital hypoplasia of the C6 pedicle and superior articulating facet, resulting in an anomalous course of the vertebral artery (VA). Observations: A 28-year-old female presented to the emergency department after a minor trauma without neurological deficits. Imaging revealed congenital hypoplasia of the right C6 pedicle and superior articulating facet, absence of the C6 transverse foramen, and anomalous entry of the right VA at the C5 transverse foramen. The patient was managed conservatively with a cervical collar and remained neurologically intact at follow-up. Lessons: This case underscores the importance of thorough radiological evaluation in identifying rare cervical spine malformations and their potential clinical significance. Recognition of such anomalies is critical for surgical planning and risk mitigation, especially during anterior cervical spine procedures. https://thejns.org/doi/10.3171/CASE25161.