Arteries, Veins and Lymphatics of the Leg Flashcards
Popliteal artery
- Femoral artery changes its name to the popliteal artery when it exits the adductor hiatus to enter the popliteal fossa
Course of popliteal artery
o Courses inferiorly through the floor of the popliteal fossa
o Crosses the knee joint lying in the intercondylar fossa
Termination of the popliteal artery
Terminates at the inferior border of the popliteus muscle by dividing into its two terminal branches - Anterior tibial artery and posterior tibial artery
Popliteal artery in the popliteal fossa
o In the fossa, the popliteal artery lies deep to the vein
o The two vessels are enclosed in a dense connective tissue sheath
o The popliteal artery is located deep in the fossa throughout its course
o Anteriorly, it lies against the capsule of the joint
o Posteriorly, it is deep to the semimembranosus muscle, popliteal vein, tibial nerve and gastrocnemius muscle
Branches of the popliteal artery
o Cutaneous branches o Muscular branches o Medial superior genicular artery o Lateral superior genicular artery o Medial inferior genicular artery o Lateral inferior genicular artery o Middle genicular artery o Posterior tibial artery o Anterior tibial artery o Sural artery
Cutaneous branches of the popliteal artery
- Supply the superficial structures of the posterior part of the leg (either directly or indirectly)
- Located between heads of gastrocnemius muscle
- Some branches follow the small saphenous vein
Muscular branches of popliteal artery
- Gives rise to 2-3 muscular branches from its proximal end
- Supplies the lower ends of the adductor magnus and hamstring muscles
Genicular arteries of popliteal artery
- Medial and lateral superior genicular arteries
- Middle genicular artery
- Medial and lateral inferior genicular arteries
Medial and lateral inferior genicular arteries
o Originate from popliteal artery distal to the knee joint
Medial inferior genicular artery
- Larger of the two
- Passes below the medial collateral ligament
- Supplies the tibia and knee joint
Lateral inferior genicular artery
- Travels laterally, superior to the head of the fibula
- Passes deep to lateral collateral ligament and the tendon of the biceps femoris
- Its branches contribute to genicular anastomosis on the anterior side of knee
Sural arteries
- A medial and lateral sural artery originate from the popliteal artery at the knee joint
- They are distributed to the gastrocnemius, soleus and plantaris muscles
Anastmosis around knee joint (genicular anastomosis)
- The knee is the largest joint in the body, needs adequate blood supply so surrounded by vessels
- Network of anastomotic vessels is located at the anterior side of the joint around the patella
Arteries included in the genicular anastomosis
o Descending genicular artery
o Medial and lateral superior genicular arteries
o Medial and lateral inferior genicular arteries
o Descending branch of the lateral femoral circumflex artery
o Anterior and posterior tibial recurrent arteries
o Circumflex fibular artery
Superficial and deep branches of the genicular anastomosis
o Superficial branches supply soft tissues around the joint
o Deeper branches supply the knee joint
Blockage of vessels in genicular anastomosis
o If there is an abrupt blockage, anastomotic network is not sufficient to supply the joint
o If there is a gradual onset blockage, the anastomosing branches can gradually increase in size to supply an adequate amount of blood to the knee joint
Anterior tibial artery
- Artery of the crural compartment
- Smaller than the posterior tibial artery
Course of anterior tibial artery
o Begins at the inferior border of popliteus muscle
o Passes anteriorly between the two heads of the tibialis posterior muscle through an opening in the upper end of the interosseous membrane to enter the anterior leg
o Descends on anterior surface of interosseous membrane in an inferomedial direction
o Accompanied by a venae comitantes (vein lies on either side of artery)
Branches of the anterior tibial artery
o Posterior tibial recurrent o Anterior tibial recurrent o Circumflex fibular o Anterior medial malleolar o Anterior lateral malleolar o Muscular branch
Termination of the anterior tibial artery
o Ends at ankle joint (midway between medial and lateral malleoli) where it becomes the dorsalis pedis artery
Posterior tibial recurrent artery (branch of anterior tibial)
- Small, inconstant branch which is usually the first branch of anterior tibial artery
- Given off before anterior tibial enters the anterior crural compartment
- Anastomoses with the inferior genicular branches to take part in genicular anastomoses
Anterior tibial recurrent (branch of anterior tibial)
- Originates close to entrance of anterior tibial artery into the anterior crural compartment
- It is distributed to the anterior part of the knee and joins the genicular anastomosis
Circumflex fibular (branch of anterior or posterior tibial)
- Small vessel which ramifies around the neck of the fibula to supply the soleus and peroneus (fibularis) longus muscle
- Artery supplies osseous and articular structures as it courses laterally around the fibular neck within the substance of the soleus muscle
- Variation: 40% of cases, arises from anterior tibial artery, 32% of cases, arises from posterior tibial artery
Anterior medial malleolar artery (branch of the anterior tibial)
- Branch of anterior tibial artery about 5 cm proximal to ankle joint
- Small vessel which travels inferomedially across the proximal extensor retinaculum, deep to extensor hallucis longus and tibialis anterior
- Ramifies around the medial malleolus
- Anastomoses with branches of the posterior tibial and medial plantar arteries
Anterior lateral malleolar artery (branch of the anterior tibial)
- Originates from lateral side of anterior tibial artery close to the origin of medial malleolar branch
- Passes deep to the tendons of extensor digitorum longus and peroneus tertius muscles to supply lateral side of ankle joint
Muscular branch of anterior tibial artery
- Muscular branches are given off to supply muscles of anterior and lateral leg compartments
- Some branches travel deep to anastomose with similar branches of the posterior tibial artery
Posterior tibial artery
Larger than anterior tibial artery
Course of posterior tibial artery
o Begins at inferior border of popliteus and has a deep course throughout its descent
o Passes deep to the origin of the soleus muscle in an inferomedial direction
o During its descent, it can be located on the posterior surface of the tibialis posterior muscle in company with the tibial nerve and two venae comitantes
o At the ankle, posterior tibial artery runs posterior to the medial malleolus
o Artery remains separate from the medial malleolus by the tendons of the tibialis posterior and flexor digitorum longus muscles
o Inferior to the medial malleolus, the artery can be located between the tendons of flexor digitorum longus and flexor hallucis longus
Branches of posterior tibial artery
o Muscular branches o Peroneal artery (fibular) o Nutrient artery to tibia o Posterior medial malleolar o Communicating branch o Medial calcaneal o Medial plantar o Lateral plantar o Circumflex fibular
Muscular branches of posterior tibial
Direct muscular branches are distributed to the following muscles: o Flexor hallucis longus o Peroneus longus o Peroneus brevis o Tibialis posterior o Soleus
Peroneal artery (branch of posterior tibial)
- Largest branch of posterior tibial artery, located deep on the fibular side of posterior leg
Course of peroneal artery
o Originates from posterior tibial artery 2 cm distal to inferior border of popliteus muscle
o Travels inferiorly along medial side of fibula
Branches of peroneal artery
o Provides a nutrient branch to the fibula
o Provides muscular branches to muscles of posterior and lateral leg compartments
o Communicating branch that joins the communicating branch of the posterior tibial
o Lateral calcaneal branches
o Posterior lateral malleolar branches
Lateral calcaneal branches of peroneal artery
- Terminal branches which are given off as the peroneal artery passes the tibiofibular articulation
- Lateral calcaneal branches then pass lateral to the side of the heel and anastomose with other branches around the heel
Posterior lateral malleolar branches
Small branches which course toward the lateral malleolus and take part in the lateral malleolar network
Nutrient artery to tibia (branch of posterior tibial)
- One of the first branches of the posterior tibial artery
- Originates just inferior to the bifurcation of the popliteal muscle
- Largest nutrient artery of a bone in the body
- Enters nutrient foramen which is located immediately distal to the soleal line on the posterior proximal portion of the tibia
Posterior medial malleolar artery (branch of posterior tibial)
- Small vessel that travels toward medial malleolus
- Contributes to malleolar network
Communicating branch (branch of posterior tibial)
- Travels laterally, deep to the flexor hallucis longus
- Joins with the communicating branch of the peroneal artery
Other branches of posterior tibial
- Medial calcaneal artery
- Medial plantar artery
- Lateral plantar artery
- Circumflex fibular artery (usually a branch of the anterior tibial artery, but does frequently originate from the posterior tibial artery)
Veins of the leg
- Posterior tibial vein
- Anterior tibial vein
- Femoral vein
- Popliteal vein
- Small saphenous vein
- Great saphenous vein
Posterior tibial vein
o Veins of posterior compartment of leg
o Accompany posterior tibial artery as venae comitantes
o Location: between superficial & deep muscles of posterior compartment
o Drain blood from posterior muscles
o Also receive blood from superficial veins
o More consistent tributaries: Peroneal venae comitantes, which accompany the fibular artery and drain blood primarily from lateral leg (posterior & lateral compartments)
Anterior tibial vein
- Superior continuation of venae comitantes
- Accompany dorsalis pedis artery
- Courses between tibialis anterior & extensor hallucis longus muscles (w/anterior tibial artery)
- At the proximal end of the leg, inferior to popliteal fossa, the vein passes through the interosseous membrane
- Then joins the posterior tibial veins
- This junction forms the popliteal vein
Femoral vein
Superior continuation of the popliteal vein at the ADDUCTOR HIATUS
Popliteal vein
- Tributaries correspond to branches of popliteal artery
- Also receives the small saphenous vein
- Formed by joining of anterior and posterior tibial veins at the distal border of the popliteus muscle
- Ascends into popliteal fossa, accompanying the artery
- Inferior end of fossa – lies medial to artery
- Upper end of fossa – lies superficial to artery
- Exits popliteal fossa through adductor hiatus
Superficial veins of the leg
- Small (lesser) saphenous
- Great saphenous
Small saphenous vein
• Continuation of lateral marginal vein
Course of small saphenous vein
o Begins along lateral aspect of foot
o Passes into leg from behind lateral malleolus
o Ascends along lateral border of tendocalcaneus
o Reaches middle, posterior leg and communicates with great saphenous & posterior tibial veins
o Proceeds superiorly, middle, posterior leg – enters popliteal fossa
o Empties into popliteal vein between the two heads of gastrocnemius
Note: may terminate in accessory saphenous or deep veins of posterior compartment of leg.
Valves in small saphenous vein
• Possesses about 7-13 valves, one of which is near its termination, accompanied by sural nerve.
Great saphenous vein
- Continuation of medial marginal vein
- Begins at medial aspect of foot, accompanies saphenous nerve ascending up medial side of leg
- Joins femoral vein to become external iliac vein
Lymphatic system of the leg
- Numerous vessels and nodes
- Closely parallel veins of the leg - the two systems of lymphatics (coincide with two systems of veins), superficial & deep
Lymph nodes
Anterior tibial lymph node & popliteal lymph node - Where lymphatics of leg drain into
Anterior tibial lymph node
- Inconsistent, but when present it is located within the anterior compartment of leg near interosseous membrane (inferior to the hiatus) where anterior tibial vessels pass through interosseous membrane
- Anterior tibial lymph node receives lymph vessels coursing with anterior tibial artery and vein
- Efferent vessels (from anterior tibial lymph node) pass to popliteal group of lymph nodes
- If absent, anterior lymph vessels drain into popliteal lymph node
Lymphatic vessels
- Course with blood vessels
- Lymphatic vessels begin as blind CAP
- Vessels that course toward nodes are afferents (arrive)
- Vessels that leave lymph nodes are efferents (exit)
Superficial lymphatic vessels
- Course with the superficial fascia
- Lie parallel to cutaneous veins only
- Medial lymphatic vessels course with the great saphenous vein and drain the medial side of the foot into the lower group of superfiical inguinal nodes
- Lateral lymphatic vessels course with the small saphenous vein and drain the lateral side of the foot into the superficial popliteal lymphnode
- Some of the lateral lymphatic vessels will cross to the medial side with the great saphenous
Deep lymphatic vessels
- Course with both arteries and veins of the anterior tibial, posterior tibial and peroneal
Lymphatic-vessel relationships in the deep lymphatic system
- Dorsalis pedis and anterior tibial vessels drain into anterior tibial nodes
- Medial and lateral plantar vessels drain into the popliteal nodes
- Posterior tibial and peroneal vessels drain into the popliteal nodes
