The vertebral arteries (VAs) represent the main blood supply for the intracranial structures of the posterior cranial fossa. Endowed with a secondary role during fetal life, during postnatal life they become the main feeders of numerous structures of the brainstem, cerebellum, thalami and a variable portion of the temporal and occipital lobes. The embryological development of the vertebral arteries was firstly described by Padget in 1948 [1], who demonstrated that they are established as longitudinal anastomoses between the intersegmental arteries from the subclavian artery to the cranio-cervical junction. This concept was further elaborated in the monumental work of Lasjaunias, Berenstein and Brugge [2], who described in detail all anatomical variations of the VA and proposed hypotheses for its embryological development.

The knowledge of the embryological development of the vertebral artery is crucial to understand its normal anatomy and the possible variants that can occur in the adult.

The aim of this article is to give a comprehensive overview of the embryological development of the VA and to summarize the possible variants of the adult and their embryological explication.