The dorsalis pedis artery is a continuation of the anterior tibial artery, supplying blood to the dorsal surface of the foot. It is a key artery responsible for delivering oxygenated blood to the foot and toes.
Location
The dorsalis pedis artery begins at the ankle joint, specifically at the anterior aspect of the ankle, where the anterior tibial artery continues beyond the ankle. It runs along the dorsum (top) of the foot, just lateral to the tendon of the extensor hallucis longus. It continues distally, moving toward the first and second toes, where it forms an anastomosis with the deep plantar branch of the lateral plantar artery, contributing to the deep plantar arch. It is located in a superficial position, making its pulse easily palpable on the dorsal surface of the foot.
Structure and Anatomy
Origin
The dorsalis pedis artery is a direct continuation of the anterior tibial artery, which supplies blood to the anterior compartment of the leg. As the anterior tibial artery descends along the leg, it passes under the extensor retinaculum at the front of the ankle and becomes the dorsalis pedis artery at the level of the ankle joint.
Course
The dorsalis pedis artery begins at the anterior aspect of the ankle, just between the medial and lateral malleoli. It runs along the dorsum (top) of the foot, traveling in a relatively straight line toward the first intermetatarsal space. As it courses distally, the artery lies superficial, just beneath the skin, making it easily accessible for pulse palpation.
The artery runs lateral to the tendon of the extensor hallucis longus and medial to the tendon of the extensor digitorum longus, making these tendons important landmarks in identifying the artery’s course.
Branches
Along its course, the dorsalis pedis artery gives off several branches that contribute to the vascular supply of the dorsal foot, metatarsal region, and toes:
- Lateral Tarsal Artery: This branch arises near the ankle and runs laterally across the dorsum of the foot to supply the tarsal bones and surrounding structures. It often anastomoses with the arcuate artery.
- Medial Tarsal Artery: These small arteries branch off medially to supply the medial tarsal bones and the soft tissues surrounding the medial aspect of the foot.
- Arcuate Artery: The arcuate artery is one of the larger branches, which typically arises near the base of the metatarsal bones. It runs transversely across the dorsum of the foot and gives off several smaller dorsal metatarsal arteries that supply the dorsal aspect of the metatarsal bones and the toes.
- Dorsal Metatarsal Arteries: These arteries arise from the arcuate artery and travel distally along the spaces between the metatarsal bones. They give rise to dorsal digital arteries, which supply blood to the toes.
Termination
The dorsalis pedis artery terminates by dividing into two primary branches:
- First Dorsal Metatarsal Artery: This branch supplies blood to the first and second toes through its dorsal digital branches. It is an important source of blood to the digits.
- Deep Plantar Artery: The deep plantar artery penetrates the sole of the foot between the first and second metatarsal bones. It anastomoses with the lateral plantar artery from the plantar side of the foot to help form the deep plantar arch. This arch plays a crucial role in supplying blood to the plantar surface of the foot and the toes.
Anatomical Relations
The dorsalis pedis artery runs superficially on the dorsal surface of the foot, lying beneath the skin and superficial fascia, making it easily accessible for clinical examination. It lies between the tendons of the extensor hallucis longus and the extensor digitorum longus, with the deep fibular (peroneal) nerve running alongside it. The artery’s proximity to these tendons and the nerve makes it an important structure in surgical interventions and clinical diagnostics.
Palpation and Surface Anatomy
The dorsalis pedis artery is located on the dorsum of the foot, and its pulse can be palpated just lateral to the tendon of the extensor hallucis longus, near the center of the foot. This easily accessible pulse site is frequently used to assess blood flow to the lower extremity.
Function
Blood Supply to the Dorsal Aspect of the Foot
The primary function of the dorsalis pedis artery is to supply oxygenated blood to the dorsal aspect of the foot. As it runs along the dorsum, the artery provides blood to the muscles, skin, and superficial tissues of the foot. This ensures that the structures responsible for movements like toe extension and maintaining the foot’s arch receive an adequate blood supply. By nourishing the dorsal region, the artery supports the proper functioning of the foot during walking, running, and other activities.
Vascularization of the Tarsal Bones and Surrounding Structures
The dorsalis pedis artery gives off several branches, such as the medial and lateral tarsal arteries, which supply blood to the tarsal bones and their surrounding soft tissues. The tarsal bones play a key role in the foot’s structure, acting as a bridge between the leg and the foot and aiding in weight distribution during movement. By supplying blood to these bones and adjacent tissues, the dorsalis pedis artery ensures the health and functionality of this crucial region.
Formation of the Arcuate Artery and Dorsal Metatarsal Arteries
One of the important branches of the dorsalis pedis artery is the arcuate artery, which runs transversely across the dorsum of the foot and gives rise to the dorsal metatarsal arteries. These arteries supply blood to the metatarsal bones and the interosseous muscles in the foot, which are responsible for fine motor control and stabilization during gait.
The dorsal metatarsal arteries also give rise to dorsal digital arteries, which supply blood to the skin, muscles, and soft tissues of the toes. Proper blood flow through these vessels is essential for maintaining healthy tissue and supporting movements like toe flexion and extension.
Contribution to the Deep Plantar Arch
Another key function of the dorsalis pedis artery is its role in forming the deep plantar arch. The artery’s deep plantar branch penetrates the sole of the foot between the first and second metatarsal bones, where it anastomoses with the lateral plantar artery to form the deep plantar arch. This arch is responsible for supplying blood to the deeper structures of the foot, including the plantar surface and the toes.
By contributing to the deep plantar arch, the dorsalis pedis artery ensures that the foot’s sole, which is critical for weight-bearing and balance, receives an adequate supply of oxygenated blood. This vascular network is essential for proper foot function and the health of the metatarsals and toes.
Oxygenation of Foot Muscles and Tendons
The dorsalis pedis artery also plays a significant role in providing oxygenated blood to the muscles and tendons on the dorsum of the foot. These include the extensor hallucis longus and extensor digitorum longus tendons, which are responsible for extending the big toe and the other toes, respectively. The artery ensures that these muscles have a constant supply of oxygen and nutrients, allowing them to function effectively during toe movement, balance, and stabilization during walking or running.
Maintenance of Tissue Viability in the Foot
The dorsalis pedis artery is essential in maintaining tissue viability in the foot. By ensuring a consistent supply of oxygenated blood to the skin, muscles, tendons, and bones of the foot, it prevents ischemia (a lack of blood flow). This is crucial for wound healing, especially in conditions like diabetes or peripheral artery disease (PAD), where blood flow may be compromised. The artery’s role in nourishing tissues helps to keep the foot healthy and prevents conditions such as ulcers, necrosis, or gangrene, which may arise from poor circulation.
Collateral Circulation and Anastomosis
The dorsalis pedis artery also contributes to collateral circulation in the foot through its anastomosis with other arteries. The connection between the dorsalis pedis artery and the lateral plantar artery via the deep plantar arch creates an alternative pathway for blood flow in the foot. This is important in situations where one artery is blocked or compromised. The dorsalis pedis artery ensures that blood can still reach the distal parts of the foot and toes, supporting overall circulation in the lower limb.
Support for Metabolic Needs of the Foot
By providing a constant supply of oxygenated blood, the dorsalis pedis artery supports the metabolic needs of the foot’s tissues. The artery delivers oxygen and nutrients required for cellular respiration and tissue repair while also removing metabolic waste products like carbon dioxide. This process is crucial in maintaining the foot’s functionality, especially during periods of physical activity when metabolic demands increase.
Clinical Significance
The dorsalis pedis artery is clinically significant due to its role as a major blood supply to the dorsal aspect of the foot and its accessibility for pulse assessment. The dorsalis pedis pulse is commonly used in clinical settings to evaluate peripheral blood flow and assess circulatory health in the lower extremity. A strong, palpable pulse indicates healthy blood flow, while a weak or absent pulse may suggest conditions such as peripheral artery disease (PAD), vascular occlusion, or arteriosclerosis.
In diabetic patients, reduced blood flow in the dorsalis pedis artery can increase the risk of foot ulcers and delayed wound healing, making the artery’s function important for overall foot health. The artery’s involvement in the formation of the deep plantar arch also makes it crucial for maintaining proper circulation in the foot, especially in the context of trauma, vascular surgeries, or reconstructive procedures.
