popliteal fossa

definition

· diamond-shaped space behind knee

· borders

· semimembranosus and semitendinosus

· tendon of biceps femoris

· heads of gastrocnemius

· floor

· popliteal surface of femur

· capsule of knee joint

· popliteus muscle

· roof

· fascia lata

· roof pierced by

· small saphenous vein

· posterior femoral cutaneous nerve

· contents

· popliteal artery and vein

· tibial and common peroneal nerves

nerves

Common peroneal nerve

· slopes downwards on lateral side

· medial to biceps tendon

· disappears into substance of peroneus longus

· lies on neck of fibula

· lies successively on

· plantaris

· lateral head of gastrocnemius

· capsule of knee joint

· fibular origin of soleus

· divides into deep and superficial peroneal nerves

Branches

Peroneal communicating nerve

· pierces roof of fossa

· runs down to join sural nerve

Lateral cutaneous nerve of calf

· peirces roof of fossa

· supplies skin over upper anterolateral leg

Genicular nerves

· superior and inferior lateral

· travel with arteries of same name

· supply lateral knee jt

· recurrent genicular

· arises in substance of peroneus longus

· perforates tibialis anterior

· supplies capsule of superior TF jt and knee jt

Tibial nerve

· runs vertically down middle of fossa

· passes deeply between heads of gastrocnemius

· passes beneath fibrous arch of soleus

· enters calf

Branches

Sural nerve

· runs down superficially between heads of gastrocnemius

· pierces fascia halfway down calf

· replaces posterior cutaneous nerve of thigh

· joins peroneal communicating nerve

· close to small saphenous nerve

Genicular nerves

· superior and inferior medial

· accompany arteries of same name

· supply medial knee joint

· middle

· accompanies artery of same name

· pierces oblique popliteal ligament

· supplies cruciates

vessels

Popliteal artery

· deepest of NV structures

· extends from adductor magnus to fibrous arch in soleus

· handsbreadth above and below knee

· 8” in length

· enters fossa on medial side of femur

· lies deep and medial to sciatic nerve

· curves laterally

· comes to lie on lateral side of tibial nerve

· curves back medially

· lies on medial side of nerve under fibrous arch

· artery lies on

· popliteal surface of femur

· oblique popliteal ligament

· popliteus muscle

· fixed to back of knee by

· fibrous tissue

· middle genicular artery

· divides under fibrous arch of soleus

· anterior and posterior tibial arteries

Branches

Genicular arteries

· five in number

1. upper medial

· crosses medial head of Gn

· passes deep to tendon of adductor magnus

· superior to upper attachment of MCL

2. upper lateral

· crosses lateral head of Gn

· passes distal to attachment of short head of biceps

3. lower medial

· passes under medial head of Gn

· passes deep to MCL

4. lower lateral

· passes under lateral head of Gn

· crosses popliteus tendon

· passes deep to LCL

· passes forwards lying on lateral meniscus

· anastomosis anterior to knee

· upper and lower genicular aa

· descending branch of lateral femoral circumflex a

· deep branch of descending genicular a

Muscular branches

· to muscles in fossa

· sural aa to heads of Gn

· end-arteries

popliteal vein

· formed by union of venae comitantes of anterior and posterior tibial aa

· receives

· short saphenous v

· tributaries that accompany branches of popliteal a

· lies between artery and nerve at all levels