Anatomy, Bony Pelvis and Lower Limb, Foot Dorsalis Pedis Artery

The dorsalis pedis artery (DPA) is the main artery of the foot. It is a continuation of the anterior tibial artery as it crosses the ankle joint. One of the primary functions of the DPA is to carry oxygenated blood to the dorsum of the foot.[1]

The main arterial supply to the leg and foot is the femoral artery which passes through the adductor hiatus in the thigh to become the popliteal artery. The popliteal artery travels through the popliteal fossa on the posterior aspect of the knee joint, before ending into two main branches: the anterior tibial artery and the tibioperoneal trunk (tibial artery). The tibioperoneal trunk then branches into the posterior tibial artery, and peroneal artery. The anterior tibial artery is most commonly the first branch and courses through the interosseous membrane, continuing down the anterior compartment of the leg running along with the deep peroneal nerve.  It ultimately becomes the dorsalis pedis artery (DPA) as it crosses over the ankle joint.[1][2] The development of the DPA is a complex process, and anatomical variations are not uncommon. Several reports have described the origin of the dorsalis pedis artery from the peroneal (fibular) artery and not a continuation of the anterior tibial artery.[3][4] The DPA is a significant landmark in palpating the pedal pulse on physical exam and involves reconstructive surgeries of the foot. The DPA also serves as a potential distal target for peripheral bypass surgery, used for limb salvage purposes in patients with ischemic foot complications.[5]

During development of the arterial system in the lower extremity, lumbar intersegmental arteries join to form the central or axial artery. This artery later anastomoses with the terminal branch of the abdominal aorta, known as the common iliac artery. As the limb bud lengthens, the axial artery becomes the sciatic artery in the thigh. The femoral artery then branches off the external iliac artery and joins the sciatic artery. The proximal part of the sciatic artery then regresses, and primitive middle and distal segments continue as the popliteal and peroneal arteries. On reaching the distal border of the popliteus muscle, branching off the popliteal artery, the anterior tibial artery arises passing ventrally between tibia and fibula becoming the DPA.[4]

The peroneal (fibular), posterior tibial and anterior tibial arteries are the three named arteries supplying the foot. The DPA is a continuation of the anterior tibial artery after it crosses the ankle joint. It runs over the dorsum of the foot, across the tarsal bones and then dives inferiorly between the first dorsal interosseous muscle heading towards the plantar aspect of the foot. The DPA divides into a small arcuate and a larger deep plantar artery which branches to dorsal metatarsal arteries and terminates as small dorsal digital arteries. Two other branches of the DPA include the medial and lateral tarsal arteries.[6]

Deep and superficial veins drain the lower extremity. The deep veins drain into the tibial veins in the calf muscles, and the superficial veins drain into the great saphenous vein and small saphenous veins. The lymphatic drainage of the leg and foot enters the popliteal lymph nodes, and subsequently the superficial and deep inguinal lymph nodes.[7]

The deep peroneal (fibular) nerve supplies the muscles on the dorsum of the foot and gives off a lateral branch and two dorsal digital nerves. The lateral branch aids in supplying the intertarsal joints and two dorsal digital nerves supply the great and the second toe. Autonomic innervation by postganglionic sympathetic nerves travels along the peripheral nerves and supplies the vascular smooth muscle of the foot. These nerve fibers cause vasoconstriction while hormones and local mediators regulate vasodilation.[6][8]