Contribution of embryology in the understanding of cervical venous system anatomy within and around the transverse foramen: a review of the classical literature.

Anatomic arrangement of venous system within the transverse foramen is a controversial topic among authors. Precise knowledge of this arrangement is necessary in imaging where vertebral artery dissection is suspected, as well as in surgical approaches of cervical spine. This knowledge objective cannot be achieved without a prerequisite knowledge of primitive venous system. We present here an update on the development of the transverse foramen venous system through a literature review. Our review of the classical literature aimed at synthesis of available related embryological knowledge and relating this synthesis to cervical vertebrae anatomy. Our findings with regard to different primitive descriptions were consistent and often complementary across the studies. The description has varied from a single vertebral vein to a single vein divided at certain areas, or even to a confluence of venous plexus. In this manner, the embryonic knowledge for instance on venous system can help us to better understand the segmental development of vertebral veins and their plexus arrangement. Furthermore, the cranial-caudal embryology, in particular of the nervous system, conveys the initial plexiform arrangement of vertebral veins, which ends into a single venous trunk joining the subclavian vein.