Anatomy of foot and ankle perforator veins

Background: The foot venous pump is located in the plantar veins, where both its anatomy and connections with the saphenous roots and the foot perforator veins are not well known, and therefore, they are underinvestigated in daily practice. The aim of this paper is to describe the unique anatomy and the functional role of the foot perforator veins and emphasize their key role during the activation of the foot venous pump. Ankle perforator veins also play a crucial role in the venous blood return, giving rise to the anterior tibial and fibular veins. Materials and methods: A total of 400 cadaveric feet from the "don des corps" of the Descartes University (Paris, France) were injected with green Neoprene latex, which was followed by an anatomical dissection and a colored segmentation of the venous system. Duplex color sonography and CT venography with 3D modeling were used to investigate the foot perforator veins and their connections with the foot venous pump and the saphenous systems in patients with venous disease. Results: Some foot perforating veins are characterized by flow that is oriented from deep to superficial veins, due to the presence of one-way valves, a unique feature in the venous system of the lower limbs. From a hemodynamic point of view, the foot veins should not be classified into deep and superficial systems, but into medial and lateral functional units. The medial unit is comprised of the medial plantar veins, the medial marginal vein, and the medial foot perforator veins. The lateral unit is comprised of the lateral plantar veins, the lateral perforator veins, and perforator veins of the calcaneus. Ankle perforator veins are mainly the dorsal perforator veins that are connected to the initial segment of anterior tibial and fibular veins and the lateral perforator veins along the distal fibula. Conclusion: Despite the small volume of blood ejected at each step, the foot venous pump plays a key role in the venous blood return of the lower limbs. The foot perforator veins are the main outlet of the foot venous pump into the superficial venous system, working from deep to superficial; therefore, they are responsible for the systolic ascending flow in both the great and small saphenous systems during foot venous pump activation.