Anatomy of the Dorsalis Pedis Artery

The dorsalis pedis artery is the main source of blood supply to the foot. Running as a continuation of the anterior tibial artery, the blood vessel carries oxygenated blood to the dorsal surface (upper side) of the foot. A weak dorsalis pedis artery pulse may be a sign of an underlying circulatory condition, like peripheral artery disease (PAD).

Anatomy

There are three main arteries in the leg that supply blood to the foot: the peroneal (fibular) artery, the posterior tibial artery, and the anterior tibial arteries. The dorsalis pedis artery in the foot is a continuation of the anterior tibial artery in the leg. As the artery passes over the ankle joint, it becomes the dorsalis pedis artery.

The artery sits on the dosum (top) of the foot, running over the tarsal bones then down toward the plantar (sole) of the foot. It lies between the two tendons of the extensor digitorum longus muscle. At the plantar side of the foot, the dorsalis pedis artery branches into dorsal metatarsal arteries and ends as small dorsal digital arteries.

Anatomical varations of the artery are not uncommon. One study found nine variations in the anatomy of the artery, including the absence of the artery. Another study found that branching variations occur in nearly 10% of the population.

Function

The dorsalis pedis artery carries oxygenated blood to the foot. Proper blood flow is necessary for the feet to maintain proper health and mobility. Reduced blood flow can cause complications like pain, ulceration, poor wound healing, or even loss of limb.

Two muscles that lie on the dorsal (top) of the foot—the extensor hallucis and the extensor digitorum brevis—receive blood supply from the dorsalis pedis artery. Nerves in the foot play a role in vasoconstriction, a normal process that controls blood distribution throughout the body.

Palpating the dorsalis pedis artery is done when a physician is checking for peripheral artery disease. A low or absent pulse may indicate vascular disease. For those with type 2 diabetes, an absent dorsalis pedis pulse is a predictor of major vascular outcomes.

Clinical Significance

Plaque (fatty deposit) buildup in the arteries can happen anywhere in the body. When fatty deposits accumulate in the arteries, and blood vessel walls become injured, they make the walls stickier.

Substances floating through your blood, like fat, proteins, and calcium then get stuck on the walls, causing the walls to grow narrower. Arteries in the lower limb are particularly prone to atherosclerosis, which can lead to decreased blood flow and cause tissue and organ damage. 

Peripheral arterial disease (PAD) is a type of atherosclerosis that occurs in the arteries in the extremities. When these arteries become blocked, muscles in the lower legs and feet become weakened and cramp. Type 2 diabetes is the most common reason for amputation of toes and feet in the U.S., often as a result of PAD.

Pain or discomfort in the legs, feet. and toes is a common symptom of PAD. Other symptoms include cold feet, discoloration of the skin, infection, and foot sores that do not heal.

People who smoke, have diabetes, high blood pressure, high cholesterol, kidney disease, are obese, and over 50 are at higher risk for PAD. Black Americans are twice as likely as White or Asian Americans to be diagnosed with PAD. People with PAD often have atherosclerosis in other parts of the body, as well.

Diagnosis of PAD is made by measuring blood pressure in the lower legs and comparing it to that of the arms. Known as ankle/brachial index (ABI), the test is a standard for detecting PAD.

A pulse volume recording (PVR), which measures blood volume changes in the legs, may also be done. This test can help determine where blockages are located. A vascular ultrasound may be done to examine blood circulation.

Treatment of PAD

Left untreated, PAD can lead to stroke, renal disease, and amputation. Treatment for PAD may include lifestyle changes, such as smoking cessation, diet changes, exercise, foot and skin care, and a walking regimen. Managing other health conditions that may be contributing to the condition is also important.

Medication may also be used to treat co-existing conditions, like high blood pressure and high cholesterol. Antiplatelet medications may reduce the risk of heart attack or stroke and Pletal (cilostazol) may be able to improve walking distance.

When lifestyle and medication are not enough, further intervention, like angiogram with endovascular intervention or surgical bypass may be needed.

Atherectomy

Atherectomy is a procedure that uses a catheter to remove plaque from the artery. The catheter is inserted into the artery through a small hole. It is performed either in the hospital or in vascular surgeons' offices. It is done in conjunction with angioplasty. Most often, it is a same-day surgical procedure, meaning the patient can go home the same day.

Angioplasty

Another procedure used to treat PAD is angioplasty. Percutaneous transluminal angioplasty involves placing a balloon inside the artery to inflate it at the point of the blockage in order to allow the blood to resume flowing. Stenting may be done in conjunction with angioplasty and involves placing a tube in the artery to hold it open. 

Once inside the blockage, the balloon is inflated to push the plaque up against the artery wall. Once complete, the balloon is deflated and removed. At this time, the stent, if used, is inserted.

Bypass surgery

Bypass surgery involves re-routing blood around a clogged artery by grafting a new pathway. The surgery is performed under general anesthesia in the hospital by a vascular surgeon.

The surgeon makes a small incision in the artery and places a graft, connecting it above and below the blockage. The graft is made from a vein or a synthetic tube. People spend between four and seven days in the hospital after bypass surgery.

Endarterectomy

Atherosclerosis endarterectomy is the surgical removal of plaque from an artery. There are generally only two locations that this is performed, in the common femoral artery, near the groin, and in the carotid artery, in the neck. The surgery is performed in the hospital under general or regional anesthetic by a vascular surgeon.

An incision is made along the artery where the blockage is located. The plaque is removed and sometimes the diseased portion of the artery is also removed. In the carotid artery, a shunt is used to temporarily reroute blood flow to the brain while the procedure is being performed, and then removed at the end of the procedure. People usually stay in the hospital for one or two days following endarterectomy.