Anatomy chapters
Arteries and veins of the lower limb
Trace arterial inflow, venous return and the main lymphatic routes from the groin to the foot.
- Femoral becomes popliteal at the adductor hiatus.
- Anterior tibial becomes dorsalis pedis; posterior tibial supplies the plantar arteries.
- Great saphenous passes anterior to the medial malleolus; small saphenous behind the lateral.
On this page
Overview
The external iliac artery becomes femoral as it passes deep to the inguinal ligament. The femoral supplies the thigh and continues through the adductor hiatus as popliteal. Tibial branches then distribute blood to the leg and foot.
Superficial veins drain towards the deep system through valved connections. Most lower-limb lymph reaches inguinal nodes, but the lateral foot has an important route through popliteal nodes.
Femoral artery and sheath
The femoral artery enters the thigh at the mid-inguinal point, halfway between the anterior superior iliac spine and pubic symphysis. In the upper femoral triangle, the femoral nerve lies lateral and the femoral vein medial to it.
The femoral sheath encloses the proximal artery, vein and a medial lymphatic compartment, the femoral canal. The nerve is outside the sheath. More distally the vein moves behind the artery, so their relationship is not identical throughout the thigh.
The artery crosses the femoral triangle, enters the adductor canal beneath sartorius, and passes through the hiatus in adductor magnus. This marks its continuation as the popliteal artery.
Mid-inguinal point uses the pubic symphysis; the midpoint of the inguinal ligament uses the pubic tubercle.
Femoral branches and proximal anastomoses
| Name | Origin/roots | Supply/action | Clinical note |
|---|---|---|---|
| Superficial epigastric | Femoral | Lower anterior abdominal wall | Crosses superficially towards abdomen |
| Superficial circumflex iliac | Femoral | Skin towards iliac crest | Superficial groin branch |
| External pudendal branches | Femoral | External genital and adjacent skin regions | Superficial and deep branches |
| Profunda femoris | Femoral | Main deep thigh supply | Gives circumflex and perforating branches |
| Medial circumflex femoral | Usually profunda | Hip and proximal femur | Retinacular branches are critical to adult femoral-head perfusion |
| Lateral circumflex femoral | Usually profunda | Anterior/lateral thigh and hip region | Descending branch joins knee network |
| Perforating arteries | Profunda | Posterior thigh after piercing adductor magnus | Connect deep thigh territories |
| Descending genicular | Distal femoral | Medial knee network | Leaves near the end of adductor canal |
The trochanteric anastomosis links gluteal and circumflex vessels near the proximal femur. The cruciate network connects inferior gluteal, transverse circumflex and first perforating branches around the posterior upper thigh.
Snell emphasises the obturator contribution through the ligament of the head in the young and circumflex supply to the neck.
In the adult, retinacular branches, especially from medial circumflex femoral, are the major practical concern after an intracapsular fracture.
An anastomosis can provide an alternative route, but adequate flow depends on the site and speed of obstruction. Gradual narrowing gives collateral channels time to enlarge; sudden interruption may overwhelm them.
Popliteal and leg arteries
The popliteal artery is the deepest major structure in the popliteal fossa, close to the femur and posterior knee capsule. Superficial to it lie the popliteal vein and tibial nerve.
It gives muscular and genicular branches before dividing at the lower border of popliteus.
Snell describes anterior and posterior tibial terminal arteries; clinical imaging often names the initial posterior pathway the tibioperoneal trunk before fibular and posterior tibial separation.
| Name | Origin/roots | Supply/action | Clinical note |
|---|---|---|---|
| Genicular network | Femoral, circumflex, popliteal and tibial branches | Collateral supply around knee | Does not guarantee perfusion after major trauma |
| Anterior tibial | Popliteal | Anterior leg, travelling with deep fibular nerve | Crosses through upper interosseous membrane |
| Dorsalis pedis | Continuation of anterior tibial at ankle | Dorsum of foot and deep plantar connection | Pulse lateral to extensor hallucis longus tendon |
| Posterior tibial | Posterior terminal pathway of popliteal | Posterior leg and plantar branches | Pulse behind medial malleolus |
| Fibular, or peroneal | Usually posterior tibial pathway | Lateral/deep posterior leg and ankle connections | Runs close to flexor hallucis longus |
The posterior tibial artery passes beneath the flexor retinaculum with its accompanying veins and tibial nerve. It lies between the flexor digitorum longus and flexor hallucis longus tendons.
Foot arteries
Dorsalis pedis gives tarsal, arcuate and metatarsal branches. Its deep plantar continuation enters the first intermetatarsal space to join the plantar circulation.
The smaller medial plantar artery serves the medial sole. The larger lateral plantar artery crosses the sole and curves medially to form the deep plantar arch with the deep plantar branch of dorsalis pedis.
Plantar metatarsal arteries give digital branches. Perforating connections link plantar and dorsal systems. The arch lies deep in the sole, unlike the superficial dorsal arterial course.
The plantar arch is formed chiefly by lateral plantar plus the deep plantar continuation of dorsalis pedis.
Superficial and deep veins
| Name | Origin/roots | Supply/action | Clinical note |
|---|---|---|---|
| Great saphenous | Medial dorsal venous network | Anterior to medial malleolus; medial leg and thigh to femoral vein | Accompanies saphenous nerve in the leg |
| Small saphenous | Lateral dorsal network | Behind lateral malleolus; posterior calf to popliteal vein | Accompanies sural nerve; termination varies |
| Perforating veins | Connections through deep fascia | Normally direct superficial blood into deep veins | Valve failure contributes to varicosities |
| Deep leg veins | Venae comitantes of tibial/fibular arteries | Join popliteal, then femoral vein | Compressed by contracting calf muscles |
The great saphenous enters through the saphenous opening in fascia lata. Near its termination it receives superficial epigastric, circumflex iliac and external pudendal tributaries.
Calf contraction compresses the deep veins. Competent valves guide blood towards the heart and prevent reflux into superficial veins. Relaxation then allows refilling: this is the muscular venous pump.
The femoral vein is a deep vein; its thrombosis is not a superficial venous event.
Lymphatic drainage
Most superficial lymph follows the great saphenous route to the vertical superficial inguinal group. The lateral foot and posterolateral calf follow the small saphenous route to popliteal nodes.
Deep lymph follows deep vessels to popliteal and deep inguinal nodes. Superficial inguinal and popliteal efferents ultimately reach deep inguinal nodes, then external iliac nodes.
Clinical relevance
Intracapsular femoral-neck fracture
How it happens: displacement tears vessels ascending along the neck under the capsule.
What you see: the femoral head may lose perfusion and later develop avascular necrosis. A patent artery in the head ligament does not reliably compensate in an adult.
Varicose veins
How it happens: valve failure allows reflux and sustained superficial venous pressure, often with incompetent perforators.
What you see: dilated tortuous superficial veins, dependent swelling and, in advanced disease, skin changes. The visible veins reflect failure of a connected drainage system.
Popliteal arterial injury
How it happens: knee displacement stretches or tears the vessel tethered across the posterior joint.
What you see: distal ischaemia may be immediate or evolve after intimal injury and thrombosis. An initial pulse does not exclude vessel damage.
Trace arterial name changes and place the nerve, vein and artery at each regional landmark. Link femoral-head perfusion to neck fractures and compare the two saphenous courses and nerve companions. Follow lateral foot lymph through popliteal nodes before deep inguinal drainage.
Quick revision
- Femoral begins beneath inguinal ligament and ends at adductor hiatus.
- Profunda and its branches supply the deep thigh.
- Popliteal artery is deep to vein and tibial nerve.
- Anterior tibial continues as dorsalis pedis.
- Posterior tibial gives medial and lateral plantar arteries.
- Great saphenous is anterior to medial malleolus; small is posterior to lateral.
Sources: Snell's Clinical Anatomy by Regions, supplied Lower Limb chapter, with current vascular terminology where noted; UHS PGET Paper I MBBS TOS. Picture links are visual study resources. Text and tables written independently for The House Job.
FAQ
Which artery supplies most of the adult femoral head?
Retinacular branches, chiefly from the medial circumflex femoral artery, are the main source clinically endangered by a displaced intracapsular neck fracture.
Where is the posterior tibial pulse?
Behind the medial malleolus, in the interval towards the heel, deep to the flexor retinaculum.
Where does the small saphenous vein usually end?
In the popliteal vein, although its termination and proximal connections vary.
Which nodes receive superficial lymph from the lateral foot?
Popliteal nodes, followed by drainage towards deep inguinal nodes.