What structure does the cephalic vein pierce before entering the axillary vein?

The cephalic vein's path is significant as it traverses various anatomical structures before draining into the axillary vein. The structure it pierces is the clavipectoral fascia, which is a connective tissue layer located beneath the pectoralis major muscle.

The clavipectoral fascia serves as a protective and supportive covering for the structures passing between the arm and the thorax, including arteries, veins, and nerves. When the cephalic vein approaches the axillary region, it must penetrate this fascia to connect with the axillary vein. This relationship is crucial as it influences the surgical considerations and potential complications related to venous access in this region.

Understanding the anatomy surrounding the cephalic vein, particularly its connection with the clavipectoral fascia, is essential for surgical practice and interventions involving the upper limb and thoracic outlet.