Transcript Anterior & Lateral comp. of leg

Lower Limb
CONTENTS OF THE ANTERIOR FASCIAL
COMPARTMENT OF THE LEG
 Muscles: The tibialis anterior, extensor
digitorum longus, peroneus tertius and
extensor hallucis longus.
 Blood supply:
 Anterior tibial artery.
 Nerve supply:
 Deep peroneal nerve.
RETINACULA OF THE ANKLE


In the region of the ankle joint,
the deep fascia is thickened to
form a series of retinacula.
They serve to keep the long
tendons in position and act as
modified pulleys.
The superior extensor
retinaculum

It is attached to the distal ends
of the anterior borders of the
fibula and tibia. Near its medial
end, it splits to enclose the
tendon of the tibialis anterior
muscle.
RETINACULA OF THE ANKLE
The inferior extensor
retinaculum



It is a Y-shaped band of deep
fascia that is attached by its
stem to the upper surface of the
calcaneum.
The upper limb of the Y is
attached to the medial malleolus
and the lower limb is
continuous with the plantar
fascia on the medial border of
the foot.
The muscles of the anterior
group of the leg pass through
the retinaculum.
ANTERIOR ASPECT OF THE
ANKLE
Structures That Pass Anterior to the Extensor Retinacula from
Medial to Lateral:
1.
2.
Saphenous nerve and great saphenous vein (in front of the medial
malleolus).
Superficial peroneal nerve (medial and lateral branches).
Structures That Pass Beneath or Through the Extensor Retinacula
from Medial to Lateral:






Tibialis anterior tendon.
Extensor hallucis longus tendon.
Anterior tibial artery with venae comitantes. V
Deep peroneal nerve.
Extensor digitorum longus tendons.
Peroneus tertius.
Anterior Compartment of Leg
Origin of the Muscles
Extensor Digitorum Longus
Tibialis Anterior Muscle
Extensor Hallucis
Peroneus Tertius
Peroneus Tertius
(Insertion)
Ext. Digitorum Longus
(Insertion)
Ext. Hallucis (Insertion)
Front of Leg
Tibialis Anterior

Origin: From the upper half
of the lateral surface of the tibia
and from the interosseous
membrane.

Insertion: The tendon passes
through both extensor
retinacula and is attached to the
medial cuneiform bone and the
adjoining base of the first
metatarsal bone.
Front of Leg
Tibialis Anterior
 Nerve supply: Deep
peroneal nerve.
 Action:
 Extends (dorsiflexes) the
foot at the ankle joint.
 Inverts the foot.
 It assists in holding up the
medial longitudinal arch
of the foot.
Front of Leg
Extensor Digitorum Longus

Origin: From the upper two
thirds of the anterior surface of the
fibula and from the interosseous
membrane

Insertion:
 The tendons pass behind the
superior and through the inferior
extensor retinacula.
 Each tendon forms an extensor
expansion with the other tendons
of the same toe and is inserted
onto: The middle and distal
phalanges of the lateral four toes.
Front of Leg
Extensor Digitorum Longus
 Nerve supply: Deep
peroneal nerve.
 Action:
 Extends the toes and
extends the foot at the
ankle joint.
Front of Leg
Peroneus Tertius

Origin:

It arises from the lower third of the
anterior surface of the fibula and the
interosseous membrane.

Insertion:
 Its tendon follows the tendons of
extensor digitorum longus behind the
superior and through the inferior
extensor retinacula.
 It is inserted into the medial side of
the dorsal aspect of the base of the
fifth metatarsal bone.
Front of Leg
Peroneus Tertius
 Nerve supply: Deep
peroneal nerve.
 Action:
 Extends the foot at the
ankle joint.
 Everts the foot.
Front of Leg
Extensor Hallucis Longus

Origin: From the middle half
of the anterior surface of the
fibula and from the interosseous
membrane.

Insertion:
 The tendon passes behind the
superior and through the
inferior extensor retinacula.
 It is inserted into the base of the
distal phalanx of the great toe.
Front of Leg
Extensor Hallucis Longus
 Nerve supply: Deep
peroneal nerve.
 Action:
 Extends the big toe
and extends the foot at
the ankle joint.
 It also assists in
inversion of the foot.
Blood Supply of the anterior
Compartment of the Leg
Anterior Tibial Artery



The anterior tibial artery is the
smaller of the terminal
branches of the popliteal artery.
It arises at the level of the lower
border of the popliteus muscle
and passes forward into the
anterior compartment of the leg
through an opening in the
upper part of the interosseous
membrane.
It descends on the anterior
surface of the interosseous
membrane, accompanied by the
deep peroneal nerve.
Anterior Tibial Artery





The nerve first lies lateral to the artery, then anterior to it
and finally lateral again.
In the upper part of its course, it lies deep beneath the
muscles of the compartment.
In the lower part of its course, it lies superficial in front of
the lower end of the tibia.
Having passed behind the superior extensor retinaculum,
it has the tendon of the extensor hallucis longus on its
medial side and the deep peroneal nerve and the tendons of
extensor digitorum longus on its lateral side.
In front of the ankle joint, the artery becomes the dorsalis
pedis artery.
Anterior tibial artery & nerve
Anterior Tibial Artery
Branches
 Muscular branches to neighboring muscles.
 Anastomotic branches that anastomose with
branches of other arteries around the knee and
ankle joints.
Venae comitantes of the anterior tibial artery join
those of the posterior tibial artery in the popliteal
fossa to form the popliteal vein.
Nerve Supply
Deep Peroneal Nerve




The deep peroneal nerve is one
of the terminal branches of the
common peroneal nerve.
It arises in the substance of the
peroneus longus muscle on the
lateral side of the neck of the
fibula.
The nerve enters the anterior
compartment by piercing the
anterior fascial septum.
It then descends deep to the
extensor digitorum longus
muscle, first lying lateral, then
anterior and finally lateral to
the anterior tibial artery.
Nerve Supply
Deep Peroneal Nerve
The nerve passes behind the
extensor retinacula.
Branches:
 Muscular branches to the
tibialis anterior, the extensor
digitorum longus, the
peroneus tertius and the
extensor hallucis longus.
 Articular branch to the ankle
joint.

Lower Limb
CONTENTS OF THE LATERAL FASCIAL
COMPARTMENT OF THE LEG
 Muscles: Peroneus longus and peroneus
brevis.
 Blood supply:
 Branches from the peroneal artery.
 Nerve supply:
 Superficial peroneal nerve.
RETINACULA OF THE ANKLE
The superior peroneal
retinaculum
 It is a thickened band
of deep fascia that
extends from the lateral
malleolus to the lateral
surface of the
calcaneum.
 The tendons of the
peroneus longus and
brevis pass deep to the
retinaculum.
RETINACULA OF THE ANKLE
The inferior peroneal
retinaculum
 It is a thickened band of
deep fascia that is attached
to the peroneal tubercle
and to the calcaneum
above and below the
peroneal tendons.
 The tendons of the
peroneus longus and brevis
pass deep to the
retinaculum.
Lateral ASPECT OF THE
ANKLE
Structures That Pass behind the Lateral Malleolus
Superficial to the Superior Peroneal Retinaculum:
A. The sural nerve.
B. Small saphenous vein.
Structures That Pass behind the Lateral Malleolus
beneath the Superior Peroneal Retinaculum:
 The peroneus longus and brevis tendons.
 The two muscles also pass beneath the inferior
peroneal retinaculum.
Lateral side of Leg
Peroneus Longus
 Origin: From the upper two
thirds of the lateral surface
of the fibula.
 Insertion:
 It is inserted into the medial
cuneiform and the base of
the first metatarsal.
 Nerve supply:
 Superficial peroneal nerve.
Lateral side of Leg
Peroneus Longus
 Action:
 Plantar flexes the foot at the
ankle joint.
 Everts the foot.
 It plays an important part in
holding up the lateral
longitudinal arch in the foot
and helps to maintain the
transverse arch of the foot.
Lateral side of Leg
Peroneus Brevis

Origin: From the lower two thirds of
the lateral surface of the fibula.

Insertion:
 It is inserted into the tubercle on the base
of the fifth metatarsal bone.

Nerve supply:
 Superficial peroneal nerve.

Action:

Plantar flexes the foot at the ankle joint.
Everts the foot.
It assists in holding up the lateral
longitudinal arch of the foot.


Artery of the Lateral Fascial
Compartment of the Leg

Numerous branches
from the peroneal
artery which lies in the
posterior
compartment of the
leg, pierce the
posterior fascial
septum and supply the
peroneal muscles.
Nerve of the Lateral Fascial
Compartment of the Leg
Superficial Peroneal Nerve
 The superficial peroneal nerve
is one of the terminal branches
of the common peroneal nerve.
 It arises in the substance of the
peroneus longus muscle on the
lateral side of the neck of the
fibula.
 It descends between the
peroneus longus and brevis
muscles and in the lower part of
the leg it becomes cutaneous.
Nerve of the Lateral Fascial
Compartment of the Leg
Superficial Peroneal Nerve
Branches:
 Muscular branches: to the peroneus
longus and brevis.
 Cutaneous: Medial and lateral
branches are distributed to the skin
on the lower part of the front of the
leg and the dorsum of the foot.
 In addition, branches supply the
dorsal surfaces of the skin of all the
toes, except the adjacent sides of the
first and second toes and the lateral
side of the little toe.
The Dorsum of the Foot
Extensor Digitorum Brevis

Origin: From the anterior part of
the upper surface of the calcaneum
and from the inferior extensor
retinaculum.

Insertion:
 The muscle gives rise to four
tendons that pass forward and
medially.
 The most medial tendon
(sometimes called tendon of
extensor hallucis brevis) is inserted
into the base of the proximal
phalanx of the big toe.
Dr. Iman Abdel Aal
Dr. Iman Abdel Aal
The Dorsum of the Foot
Extensor Digitorum Brevis
 The lateral three tendons join
the long extensor tendons
passing to the second, third and
fourth toes.
 Nerve supply: Deep peroneal
nerve.
 Action:
 Extends the first, second, third
and fourth toes at the
interphalangeal and
metatarsophalangeal joints.
ARTERY OF THE DORSUM OF THE
FOOT
Dorsalis Pedis Artery (the
Dorsal Artery of the Foot)


The dorsalis pedis artery begins
in front of the ankle joint as a
continuation of the anterior
tibial artery.
It terminates by passing
downward into the sole between
the two heads of the first dorsal
interosseous muscle, where it
joins the lateral plantar artery
and completes the plantar arch.
ARTERY OF THE DORSUM OF THE
FOOT
Dorsalis Pedis Artery



It is superficial in position and
is crossed by the inferior
extensor retinaculum and the
first tendon of extensor
digitorum brevis.
On its lateral side lie the
terminal part of the deep
peroneal nerve and the extensor
digitorum longus tendons.
On the medial side lies the
tendon of extensor hallucis
longus.
ARTERY OF THE DORSUM OF THE
FOOT
Dorsalis Pedis Artery
Branches
 Lateral tarsal artery: which
crosses the dorsum of the foot just
below the ankle joint.
 Arcuate artery: which runs
laterally under the extensor
tendons opposite the bases of the
metatarsal bones. It gives off
metatarsal branches to the toes.
 First dorsal metatarsal artery:
which supplies both sides of the
big toe.