Embryological and comparative description of the cephalic vein joining the external jugular vein: A case report.

The cephalic vein arises from the radial end of the dorsal venous arch. It turns around the radial border of the forearm and passes proximally along the arm to the shoulder, where it enters the axillary vein by penetrating the clavipectoral triangle. The cephalic vein is prone to vary at the antecubital fossa, where it forms numerous anastomoses. A male cadaver fixated with a 10% formalin solution was dissected during regular anatomy lessons. It was found that the cephalic vein crossed the upper third of the arm between two fasciculi of the deltoid muscle and reached the shoulder, where it passed above the acromion and crossed the posterior border of the clavicle in order to join the external jugular vein. The cephalic vein is one of the most used veins for innumerous activities, such as venipunctures and arteriovenous fistula creation. Furthermore, it is an anatomical landmark known for its consistent anatomy, as it possesses low rates of variability. Despite that, its anatomical variations are clinically and surgically significant and healthcare professionals must be aware of the variations of this vessel. We aim to report a rarely described variation of the cephalic vein and discuss its embryological, phylogenetic and clinical features.