In Depth: Vessels
Oxygenated blood leaves the heart and travels down the large thoracic aorta before the aorta splits into two main branches near the abdomen. From there, it travels down the femoral artery in the leg where it continues into other arterial branches before reaching the foot.
The major players in circulating oxygenated blood to the foot include:
- Popliteal artery: A branch of the femoral artery, the popliteal artery branches further to supply blood to the knee, thigh, and calf. It ends at the anterior and posterior tibial arteries.
- Posterior tibial artery: This branch of the popliteal artery supplies oxygenated blood to the leg and sole of the foot. It runs on the inside of the leg and is accompanied by the posterior tibial vein.
- Anterior tibial artery: The other branch of the popliteal artery from the back of the knee, this artery supplies blood to the muscles of the leg and foot.
- Peroneal artery: This is the largest branch of the posterial tibial artery. It supplies blood to the outside and back of the ankle and calf muscles. It ends at the lateral calcaneal artery.
- Plantar arteries: The plantar arteries—lateral, medial, and deep—form a looping web of arteries across the foot and down through each toe. They unite with the dorsalis pedis artery.
- Dorsalis pedis: This artery supplies blood to the surface of the foot as a continuation of the anterior tibial artery. It is accompanied by the dorsalis pedis vein.
The veins of the foot circulate deoxygenated blood from the tissues back to the heart. As the heart pumps the blood returning to it against gravity, problems can arise.
Circulation problems of the foot are common in older and obese people and those who stand for long periods of time. One common problem is varicose veins. These are swollen, twisted veins that sometimes cause pain due to an abnormal collection of blood. Malfunctioning valves that allow blood to pool in the vein normally cause this. These veins can usually be seen through the skin.
Nerves in the feet send messages, such as indications of heat and pain and other information, to the brain. The dorsal digital nerves of the foot branch throughout the body of the foot and down through each toe. They are themselves branches of the larger intermediate dorsal cutaneous nerve, medial dorsal cutaneous nerve, sural nerve, and deep fibular nerve in the lower extremities.