The Lower LimbThe Lower Limb

Popliteal Fossaa diamond shaped intermuscular space situated at the back of the knee

the fossa is most prominent when the knee joint is flexed.

Contains:

Popliteal vessels

small saphenous veins

common peroneal and tibial nerves

posterior cutaneous nerve of the thigh

genicular branch of the obturator nerve

connective tissue and lymph nodes

Popliteal Fossa

BOUNDARIES

Laterally: biceps femoris and lateral head of gastrocnemius and plantaris

Medially: semimembranosus and semitendinosus above and medial head of gastrocnemius below

Anterior wall or floor: popliteal surface of femur, posterior ligament of knee joint and politeus muscle

roof: skin, superficial fascia and deep fascia of thigh

Popliteus MuscleORIGIN

Lateral surface of the lateral condyle of femur

INSERTIONAttached to posterior surface of tibia, above the soleal line

NERVE SUPPLY Tibial nerve

ACTION

• medial rotation of tibia on femur• lateral rotation of femur on tibia (if foot is on the ground)• flexion of the knee

Popliteal Arterydeeply placed and enters the popliteal fossa through the opening of adductor magnus as a continuation of adductor magnus

it ends at the level of the lower border of popliteus muscle by dividing into anteror and posterior tibial arteries

Anteriorly: popliteal surface of femur, knee joint and popliteus muscle

Posteriorly: popliteal vein, tibial nerve, fascia and skin

Branches

muscular branches and

articular branches of knee

Popliteal Vein

formed by the junction of the venae comitantes of the anterior and posteror tibial arteries at the lower border of politeus muscle on the medial side of politeal artery

As it ascends through the fossa, it crosses behind the politeal artery so that it comes to lie on its lateral side.

it passes through the opening in the adductor magnus to become femoral vein

Popliteal Vein

TRIBUTARIES

Veins that correspond to branches given off by the popliteal artery

Small Saphenous vein

Arterial anastomosis around the knee joint

To compensate for the narrowing of the popliteal artery, which occurs during extreme flexion of knee, around the knee joint is a profuse anastomosis of small branches of femoral artery with muscular and articular branches of popliteal artery and with branches of anterior and posterior tibial arteries

Popliteal Lymph Nodes

about six lymph nodes are embedded in the fatty connective tissue of popliteal fossa

receive superficial lymph vessels from the lateral side of foot and leg

accompany small saphenous vein into the popliteal fossa

receive lymph from knee joint and from deep lymph vessels accompanying the anterior and posterior tibial arteries

Tibial Nerve

larger terminal branch of sciatic nerve that enters the popliteal fossa

arises in the lower third of thigh

runs downward through the popliteal fossa, lying first on the lateral side of popliteal artery, then posterior and finally medial to it.

Tibial Nerve

BRANCHES

Cutaneous: sural nerve

Muscular branches supply both heads of gastrocnemius, plantaris, soleus and popliteus

Articular branches supply the knee joint

Common Peroneal Nervesmaller terminal branch of sciatic

nerve

arises in the lower third of thigh

runs downward through the popliteal fossa following the medial border of biceps muscle

leaves the fossa by crossing superficially the lateral head of gastrocnemius muscle

passes behind the head of fibula winds laterally around the neck bone, pierces the peroneus longus muscle and divides into two terminal branches:

superficial peroneal nerve

deep peroneal nerve

Common Peroneal Nerve

Branches:

Cutaneous: sural communicating branch runs downward and joins sural nerve and lateral cutaneous nerve of calf that supplies skin on the lateral side of the back of the leg

Muscular branch to the short head of biceps femoris muscle, which arises high up in the popliteal fossa

Articular branches to the knee joint

Posterior Cutaneous of the thigh

A branch of sacral plexus

terminates by supplying the skin over the popliteal fossa

Obturator Nerve

leaves the subsartorial canal with the femoral artery by passing through the opening in the adductor magnus

terminates by supplying knee joint

Facial compartments of Leg

the deep fascia surrounds the leg and is continous above with the deep fascia of thigh

it is attached to the anterior and medial borders of tibia

two intermuscular septa pass from its deep aspect to be attached to fibula

these, together divide the leg into three compartments

anterior, lateral and posterior each having its own muscles, blood supply and nerve supply

Facial compartments of Leg

INTEROSSEROUS MEMBRANE

binds the tibia and fibula together and provides attachment for neighboring muscles

Facial compartments of Leg

RETINACULA OF ANKLE

thickenings of deep fascia that keep the long tendons around the ankle joint in position and act as pulleys

Inferior Peroneal Retinaculum

binds the tendons of the peroneus longus and brevis muscles to lateral side of calacaneum

Facial compartments of Leg

RETINACULA OF ANKLE

Superior Extensor Reticulum

attached to the distal ends of anterior borders of fibula and tibia

Inferior Extensor Reticulum

Y shaped band loacated in front of ankle joint

Facial compartments of Leg

RETINACULA OF ANKLE

Flexor Retinaculum

extends from medial malleolus downward and backward to be attached to the medial surface of calcaneum

binds the tendons of the deep muscles of the back of leg to the back of medial malleolus as they pass forward to enter the sole

Facial compartments of Leg

RETINACULA OF ANKLE

Superior Peroneal Retinaculum

connects the lateral malleolus to the lateral surface of calcaneum

binds the tendons of peroneal longus and brevis to the back of lateral malleolus

Inferior Peroneal Retinaculum

binds the tendons of peroneal longus and brevis muscles to lateral side of calcaneum

Facial Compartments of Leg

Skin

Cutaneous Nerves

Lateral cutaneous of calf - branch of common peroneal nerve, supplies skin on the upper part of lateral surface of leg

Superficial peroneal nerve - branch ofbranch of common peroneal nerve, supplies the skin of the lower part of anterolateral surface of leg

Saphenous nerve - branch of femoral nerve, supplies the skin on anteromedial surface of leg

Facial Compartments of Leg

Skin

Superficial Veins

numerous small veins curve around the medial aspect of leg and ultimately drain into the great saphenous vein

Facial Compartments of Leg

Skin

Lymh Vessels

the greater part of lymph from skin and superficial fascia on the front of the leg drains upward and medially in vessels that follow the great saphenous vein, to end in the vertical group of superficial inguinal lymph nodes.

a small amount of lymph from the upper lateral part of the front of the leg may pass via vessels that accompany the small saphenous vein and drain into the popliteal nodes

Contents of the anterior Fascial Compartment of the

Leg

Muscles: tibialis anterior, extensor digitorum longus, peroneus tertius and extensor extensor hallucis longus

Blood Supply: Anterior tibial artery

Nerve Supply: Deep peroneal nerve

Contents of the anterior Fascial Compartment of the Leg

Muscles of the anterior Fascial compartment of LegMuscles of the anterior Fascial compartment of Leg

muscle origin insertion Nerve Supply nerve root Action

Tibialis anterior

lateral surface of shaft of tibia and

interosserous membrane

Medial cuneiform and base of 1st metatarsal

bone

Deep peroneal

nerveL4, 5

extends foot at ankle joint, inverts

foot at subtalar and transverse

trasal joints; holds up medial

longitudinal arch of foot

Extensor digitorum longus

Anterior surface of shaft of tibula

extensor expansion of lateral four toes

deep peroneal

nerveL5, S1

Extends toes; extends foot at

ankle joint

Peroneus tertiusAnterior surface of

shaft of tibulabase of 5th metatarsal

bone

Deep peroneal

nerveL5, S1

extends foot at ankle joint; everts

foot at subtalar and transverse

tarsal joints

Extensor hallucis longus

anterior surface of shaft of tibula

base of distal phalanx of great toe

Deep peroneal

nerveL5, S1

Extends big toe and foot at ankle joint; inverts foot at subtalar and

transverse tarsal joint

extensor digitorum brevis

Calcaneum

by four tendons into the proximal phalanx of big toe and long extensor

tendons to 2nd, 3rd and 4th toes

deep peroneal

nerveL5, S1 Extends toes

Contents of the anterior Fascial Compartment of the Leg