Download Vascular Anatomy of the Lower Extremities

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Vascular Anatomy of the Lower Extremities
The external iliac artery becomes the common femoral
artery after passing under the inguinal ligament. The
common femoral artery and vein are enveloped by the
femoral sheath. Scarpa’s triangle is defined by the adductor longus muscle medially, the Sartorious muscle laterally, and by the inguinal ligament superiorly. The femoral
vessels and nerves are in the following orientation lateral
to medial: femoral nerve, femoral artery, femoral vein,
and lymphatics (NAVeL). The common femoral artery
gives off several branches that include the superficial
epigastric artery, the superficial circumflex artery, and
the superficial and deep external pudendal arteries. The
fossa ovalis is a medial opening in the fascia lata where
the saphenous vein enters the femoral triangle. Approximately 4 cm below the inguinal ligament, the common
femoral artery splits into the superficial femoral artery
and the profunda (deep femoral artery). The profunda
courses medially and posteriorly to the femur, giving rise
to medial and lateral femoral circumflex arteries and
perforating branches to supply the muscles of the flexor
compartment and the femur. An important junction is
created between the geniculate arteries of the knee and
the descending branch of the lateral femoral circumflex
artery. This creates a source of collateral blood flow when
the superficial femoral artery is occluded.
The superficial femoral artery continues inferiorly
through the adductor canal (Hunter’s canal) after the
origin of the profunda. Hunter’s canal begins at the apex
of the femoral triangle. It is bordered by the vastus medialis on the anterolateral aspect, the adductor longus
muscle on the posterior border, and by the Sartorious
muscle superiorly. Hunter’s canal contains the superficial
femoral artery, the saphenous nerve, and the nerve to the
vastus medialis. The saphenous nerve departs the canal
through the adductor hiatus to join the saphenous vein,
traveling toward the medial ankle and foot.
The adductor hiatus marks the end of the superficial
femoral artery and the beginning of the popliteal artery.
The popliteal artery travels inferiorly between the
femoral condyles and deep to the soleus muscle. As the
popliteal artery courses through the popliteal fossa, it
gives multiple branches of geniculate arteries (superior
lateral and medial geniculate arteries, inferior lateral and
medial geniculate arteries). The popliteal vein lies posterolateral to the artery in the adductor hiatus, dorsal to
the artery behind the knee, and then moves medial to the
artery inferiorly. The small saphenous vein joins the
popliteal vein in the popliteal fossa.
Approximately 3 cm below the knee, the popliteal
artery bifurcates into the anterior tibial artery and the
tibioperoneal trunk. The anterior tibial artery exits the
deep posterior compartment through the interosseous
membrane and enters the anterior compartment medial
to the fibula. Here it is joined by the deep peroneal nerve
and continues to travel through the anterior compartment toward the dorsum of the foot.
The dorsalis pedis artery begins as a continuation of
the anterior tibial artery beginning anterior to the ankle
joint. The dorsalis pedis artery traverses the dorsum of
the foot in between the tendons of the extensor hallucis
longus and the extensor digitorum longus. The dorsalis
pedis has named branches, including the tarsal arteries
(medial and lateral), the arcuate artery, and the first
dorsal metatarsal artery. The metatarsal arteries (second,
third, and fourth) arise from the arcuate artery. The dorsalis pedis artery terminates as the deep plantar artery
and joins the plantar arch on the sole of the foot.
The tibioperoneal trunk travels in the deep posterior
compartment approximately 3 cm distally and then
divides into the posterior tibial artery and the peroneal
artery. The posterior tibial artery travels along with
the tibial nerve in a medial course toward the medial
malleolus. The peroneal artery travels in a lateral
direction toward the ankle medial to the fibula. It terminates in branches to the ankle and the heel. The posterior tibial artery passes posterior to the medial malleolus
and terminates into the medial and lateral plantar arteries. The plantar arch is formed from a communication
between the deep plantar artery and the lateral plantar
artery.
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