The front of the leg pdf - Lower limb

Basic Anatomy

tal ends of the anterior borders of the fibula and the tibia

The superior extensor retinaculum is attached to the dis

Superior Extensor Retinaculum

481

(Figs. 10.46, 10.47, and 10.50).

The inferior extensor retinaculum is a Y-shaped band

Inferior Extensor Retinaculum

located in front of the ankle joint (Figs. 10.44, 10.46, and

The superior peroneal retinaculum connects the lateral

Superior Peroneal Retinaculum

lined by a synovial sheath.

tendons lie in compartments (Fig. 10.48), each of which is

medial malleolus as they pass forward to enter the sole. The

the deep muscles of the back of the leg to the back of the

face of the calcaneum (Fig. 10.49). It binds the tendons of

downward and backward to be attached to the medial sur

The flexor retinaculum extends from the medial malleolus

Flexor Retinaculum

synovial sheath.

ments (Figs. 10.48 and 10.50), each of which is lined by a

10.47). Fibrous bands separate the tendons into compart

malleolus to the lateral surface of the calcaneum (Fig. 10.49).

big
toe

peroneus
longus

anterior border
of tibia

tibialis anterior

extensor hallucis longus

superficial peroneal nerve

extensor digitorum longus

superior extensor
retinaculum

medial malleolus

great saphenous vein

extensor digitorum longus

dorsalis pedis artery

peroneus
brevis

superficial
peroneal nerve

inferior extensor
retinaculum

lateral
malleolus

peroneus longus
and brevis tendons

extensor digitorum
brevis

peroneus
tertius

dorsal
venous
network

extensor
hallucis
longus

FIGURE 10.46

Dissection of the front of the right leg and

mon peroneal nerve (see page 479), supplies the skin of the

a branch of the com

superficial peroneal nerve,

The

on the upper part of the lateral surface of the leg (Fig. 10.1).

common peroneal nerve (see page 479), supplies the skin

a branch of the

lateral cutaneous nerve of the calf,

The

Cutaneous Nerves

retinacula is described on pages 490.

The arrangement of the tendons beneath the different

mon sheath.

synovial sheath, which is continuous above with the com

of the calcaneum (Fig. 10.49). The tendons each possess a

the peroneus longus and brevis muscles to the lateral side

The inferior peroneal retinaculum binds the tendons of

Inferior Peroneal Retinaculum

with a common synovial sheath.

the back of the lateral malleolus. The tendons are provided

It binds the tendons of the peroneus longus and brevis to

dorsum of the foot.

The Front of the Leg

Skin

lower part of the anterolateral surface of the leg (Fig. 10.2).

joint along with the other muscles in this compartment

The peroneus tertius muscle extends the foot at the ankle

of the foot away from the ground.

Extension, or dorsiflexion of the ankle, is the movement

Note the following:

10.48, and 10.49 and are described in Table 10.5.

The muscles are seen in Figures 10.44, 10.45, 10.46, 10.47,

Muscles of the Anterior Fascial Compartment

Deep peroneal nerve

Nerve supply:

Anterior tibial artery

Blood supply:

gus, peroneus tertius, and extensor hallucis longus

The tibialis anterior, extensor digitorum lon

Muscles:

(Fig. 10.4).

the small saphenous vein and drain into the popliteal nodes

of the front of the leg may pass via vessels that accompany

10.4). A small amount of lymph from the upper lateral part

the vertical group of superficial inguinal lymph nodes (Fig.

in vessels that follow the great saphenous vein, to end in

fascia on the front of the leg drains upward and medially

The greater part of the lymph from the skin and superficial

Lymph Vessels

(Fig. 10.51).

the leg and ultimately drain into the great saphenous vein

Numerous small veins curve around the medial aspect of

Superficial Veins

face of the leg (Fig. 10.2).

(see page 463), supplies the skin on the anteromedial sur

a branch of the femoral nerve

saphenous nerve,

The

Contents of the Anterior Fascial

Compartment of the Leg

■

of the Leg

■

482

CHAPTER 10

The Lower Limb

ligamentum patellae

tibialis anterior

extensor digitorum longus

peroneus longus

peroneus brevis

superficial peroneal nerve

superior extensor retinaculum

lateral malleolus

inferior extensor retinaculum

extensor digitorum brevis

extensor digitorum longus

extensor hallucis longus

dorsalis pedis artery

deep peroneal nerve

medial malleolus

extensor hallucis longus

soleus

gastrocnemius

great saphenous vein

saphenous nerve

sartorius

peroneus tertius

extensor digitorum brevis

FIGURE 10.47

Structures in the anterior and lateral aspects of the right leg and the dorsum of the foot.

tibialis anterior

inferior extensor retinaculum

saphenous nerve

great saphenous vein

talus

medial malleolus

flexor retinaculum

tibialis posterior

flexor digitorum longus

posterior tibial artery

tibial nerve

flexor hallucis longus

plantaris tendon

tendo calcaneus

small saphenous vein

sural nerve

peroneus brevis and longus

posterior talofibular ligament

superior peroneal retinaculum

lateral malleolus

deep peroneal nerve

peroneus tertius

extensor digitorum longus

dorsalis pedis artery

extensor hallucis longus

FIGURE 10.48

Relations of the right ankle joint.

Basic Anatomy

483

flexor hallucis longus

peroneal
artery

tendo
calcaneus

abductor digiti minimi

inferior peroneal retinaculum

fifth metarsal
bone

inferior extensor retinaculum

synovial sheath

superior peroneal retinaculum

lateral malleolus

peroneus longus

peroneus brevis

tibia

tibialis posterior

flexor digitorum longus

posterior tibial artery

tibial nerve

flexor hallucis longus

medial malleolus

tibialis anterior

flexor hallucis longus

medial plantar nerve

medial plantar artery

lateral plantar artery

lateral plantar nerve

abductor hallucis

flexor digitorum brevis

medial
calcaneal
nerve and
artery

tendo
calcaneus

flexor
retinaculum

FIGURE 10.49

Structures passing behind the lateral malleolus

dons are shown in

. Synovial sheaths of the ten

(A) and the medial malleolus (B)

blue. Note the positions of the retinacula.

peroneus brevis

peroneus longus

sural nerve

superior extensor retinaculum

tendo calcaneus

lateral malleolus

small saphenous vein

peroneus longus

peroneus brevis

extensor digitorum
longus

superficial peroneal
nerve

inferior extensor
retinaculum

extensor
digitorum brevis

extensor
digitorum
longus

dorsal venous arch

reflected skin

tibialis anterior

FIGURE 10.50

Dissection of the right ankle region showing the structures passing behind the lateral malleolus. Note the posi-

tion of the retinacula.

484

CHAPTER 10

The Lower Limb

dorsal venous network

big toe

medial malleolus of tibia

great saphenous vein

FIGURE 10.51

Dissection of the right ankle region showing the origin of the great saphenous vein from the dorsal venous

arch. Note that the great saphenous vein ascends in front of the medial malleolus of the tibia.

Muscles of the Anterior Fascial Compartment of the Leg

T A B L E 1 0 . 5

and long extensor tendons to

proximal phalanx of big toe

By four tendons into the

foot at subtalar and

foot at ankle joint; inverts

Extends big toe; extends

everts foot at subtalar and

Extends foot at ankle joint;

Tibialis

Muscle

Origin

Insertion

Nerve Supply

Nerve Root

Action

Lateral surface of

shaft of tibia and

interosseous

membrane

Medial cuneiform and base of

1st metatarsal bone

Deep peroneal

nerve

L4, 5

Extends

foot at ankle joint;

inverts foot at subtalar

and transverse tarsal

joints; holds up medial

longitudinal arch of foot

Extensor

digitorum

longus

Anterior surface of

shaft of fibula

Extensor expansion of lateral

four toes

Deep peroneal

nerve

L5; S1

Extends toes; extends foot

at ankle joint

Peroneus

tertius

Anterior surface of

shaft of fibula

Base of 5th metatarsal bone

Deep peroneal

nerve

L5; S1

transverse tarsal joints

Extensor

hallucis

longus

Anterior surface of

shaft of fibula

Base of distal phalanx of

great toe

Deep peroneal

nerve

L5; S1

transverse tarsal joints

Extensor

digitorum

brevis

Calcaneum

second, third, and fourth toes

Deep peroneal

nerve

S1, 2

Extends toes

The predominant nerve root supply is indicated by boldface type.

Extension, or dorsiflexion, of the ankle is the movement of the foot away from the ground.

Basic Anatomy

485

medial

malleolus

tendon of

tibialis

lateral

malleolus

tendons of

extensor

digitorum

longus

tendons of
extensor
digitorum
longus

tendon of
tibialis
anterior

great saphenous
vein

medial
malleolus

lateral
malleolus

sites for
palpation
of dorsalis
pedis artery

FIGURE 10.52

-old woman showing inversion

Anterior view of the ankles and feet of a 29-year

sor digitorum longus on its lateral side. It is here that its

and the deep peroneal nerve and the tendons of exten

tendon of the extensor hallucis longus on its medial side

passed behind the superior extensor retinaculum, it has the

the lower end of the tibia (Figs. 10.44 and 10.47). Having

the lower part of its course, it lies superficial in front of

it lies deep beneath the muscles of the compartment. In

peroneal nerve (Fig. 10.44). In the upper part of its course,

of the interosseous membrane, accompanied by the deep

membrane (Fig. 10.42). It descends on the anterior surface

through an opening in the upper part of the interosseous

passes forward into the anterior compartment of the leg

lower border of the popliteus muscle (see page 477) and

branches of the popliteal artery. It arises at the level of the

The anterior tibial artery is the smaller of the terminal

Anterior Tibial Artery

Artery of the Anterior Fascial Compartment

with the insertion of extensor digitorum in the hand.)

inserted into the base of the distal phalanx. (Compare

middle phalanx, and the two lateral parts converge to be

part of the expansion is inserted into the base of the

. The central

extensor expansion

expansion called the

surface of each toe become incorporated into a fascial

The extensor digitorum longus tendons on the dorsal

peroneal nerve.

cles but receives no innervation from the superficial

joints along with the peroneus longus and brevis mus

also everts the foot at the subtalar and transverse tarsal

and is supplied by the deep peroneal nerve. The muscle

of the right foot.

and eversion

(A)

(B)

■

of the Leg

pulsations can easily be felt in the living subject. In front of

to the ankle joint

Articular branch

hallucis longus

digitorum longus, the peroneus tertius, and the extensor

to the tibialis anterior, the extensor

Muscular branches

Branches

the foot is described on page 498.

passes behind the extensor retinacula. Its further course in

lateral to the anterior tibial artery (Fig. 10.44). The nerve

longus muscle, first lying lateral, then anterior, and finally

septum. It then descends deep to the extensor digitorum

the anterior compartment by piercing the anterior fascial

side of the neck of the fibula (Fig. 10.44). The nerve enters

the substance of the peroneus longus muscle on the lateral

of the common peroneal nerve (see page 479). It arises in

The deep peroneal nerve is one of the terminal branches

Deep Peroneal Nerve

Compartment of the Leg

Nerve Supply of the Anterior Fascial

form the popliteal vein.

of the posterior tibial artery in the popliteal fossa to

of the anterior tibial artery join those

Venae comitantes

of other arteries around the knee and ankle joints

that anastomose with branches

Anastomotic branches

to neighboring muscles

Muscular branches

Branches

(see page 498).

the ankle joint, the artery becomes the dorsalis pedis artery

■

486

CHAPTER 10

The Lower Limb

Anterior Compartment of the Leg Syndrome

deep fascia and thus decompress the area and prevent anoxic

ment of the leg by making a longitudinal incision through the

peroneal nerve—that is, the skin cleft between the first and

Loss of sensation is limited to the area supplied by the deep

gus, and the extensor hallucis longus muscles are paralyzed.

disappears. The tibialis anterior, the extensor digitorum lon

cut off by compression, and the dorsalis pedis arterial pulse

in pressure. In severe cases, the arterial supply is eventually

the venous return is diminished, thus producing a further rise

of the ankle also increases the pain. As the pressure rises,

that pass through the compartment by passive plantar flexion

increases the severity of the pain. Stretching of the muscles

can become severe. Dorsiflexion of the foot at the ankle joint

compartment of the leg that is characteristic of this syndrome

diagnosis is critical. The deep, aching pain in the anterior

associated with bone fractures is a common cause, and early

from an increased production of tissue fluid. Soft tissue injury

increase in the intracompartmental pressure that results

The anterior compartment syndrome is produced by an

second toes. The surgeon can open the anterior compart-

necrosis of the muscles.

C L I N I C A L N O T E S

Contents of the Lateral Fascial

It arises in the substance of the peroneus longus muscle on

branches of the common peroneal nerve (see page 479).

The superficial peroneal nerve is one of the terminal

Superficial Peroneal Nerve

Nerve of the Lateral Fascial Compartment

muscles.

pierce the posterior fascial septum, and supply the peroneal

488), which lies in the posterior compartment of the leg,

Numerous branches from the peroneal artery (see page

Artery of the Lateral Fascial Compartment

tie to the transverse arch of the foot.

foot. In addition, the peroneus longus tendon serves as a

role in holding up the lateral longitudinal arch in the

and transverse tarsal joints. They also play an important

foot at the ankle joint and evert the foot at the subtalar

Both the peroneus longus and brevis muscles flex the

Note the following:

10.48, 10.49, and 10.50 and described in Table 10.6.

The muscles are seen in Figures 10.44, 10.45, 10.46, 10.47,

Muscles of the Lateral Fascial Compartment

Superficial peroneal nerve

Nerve supply:

Branches from the peroneal artery

Blood supply:

Peroneus longus and peroneus brevis

Muscles:

Compartment of the Leg

■

of the Leg

■

of the Leg

Muscles of the Lateral Fascial Compartment of the Leg

T A B L E 1 0 . 6

Muscle

Origin

Insertion

Nerve Supply

Nerve Root

Action

Peroneus

longus

Lateral surface of

shaft of fibula

Base of 1st

metatarsal

and the medial

cuneiform

Superficial

peroneal nerve

L5; S1, 2

Plantar flexes foot at ankle joint;

everts foot at subtalar and

transverse tarsal joints; supports

lateral longitudinal and transverse

arches of foot

Peroneus

brevis

Lateral surface of

shaft of fibula

Base of 5th

metatarsal bone

Superficial

peroneal nerve

L5; S1, 2

Plantar flexes foot at ankle joint;

everts foot at subtalar and

transverse tarsal joint; supports

lateral longitudinal arch of foot

The predominant nerve root supply is indicated by boldface type.

Tenosynovitis and Dislocation of the Peroneus

retinaculum must be torn. It usually occurs in older children

malleolus. For this condition to occur, the superior peroneal

Tendon dislocation can occur when the tendons of peroneus

Treatment consists of immobilization, heat, and physiotherapy.

Tenosynovitis (inflammation of the synovial sheaths) can

Longus and Brevis Tendons

affect the tendon sheaths of the peroneus longus and bre-

vis muscles as they pass posterior to the lateral malleolus.

longus and brevis dislocate forward from behind the lateral

and is caused by trauma.

C L I N I C A L N O T E S

Basic Anatomy

the ground.

ning by using the foot as a lever and raising the heel off

the main forward propulsive force in walking and run

powerful plantar flexors of the ankle joint. They provide

Together, the soleus, gastrocnemius, and plantaris act as

Note the following:

described in Table 10.7.

The muscles are seen in Figures 10.45 and 10.53 and are

of the Leg: Superficial Group

Muscles of the Posterior Fascial Compartment

Tibial nerve

Nerve supply:

Posterior tibial artery

Blood supply:

gus, flexor hallucis longus, and tibialis posterior

Popliteus, flexor digitorum lon

Deep group of muscles:

and soleus

Gastrocnemius, plantaris,

Superficial group of muscles:

superficial and deep groups (see Fig. 10.45).

divides the muscles of the posterior compartment into

of the leg is a septum that

deep transverse fascia

The

liteal nodes (Fig. 10.4).

group of superficial inguinal nodes or drain into the pop

around the medial side of the leg to end in the vertical

the back of the leg drain upward and either pass forward

Lymph vessels from the skin and superficial fascia on

Lymph Vessels

great saphenous vein.

division joining the popliteal and the other joining the

join the great saphenous vein; or it may split in two, one

subject to variation: It may join the popliteal vein; it may

The mode of termination of the small saphenous vein is

medially and join the great saphenous vein (Fig. 10.19)

that run upward and

anastomotic branches

Important

with the deep veins of the foot

Communicating veins

from the back of the leg

small veins

Numerous

Tributaries

small saphenous vein has numerous valves along its course.

and 10.40); it ends in the popliteal vein (see page 478). The

muscle in the lower part of the popliteal fossa (Figs. 10.19

fascia and passes between the two heads of the gastrocnemius

up the middle of the back of the leg. The vein pierces the deep

lows the lateral border of the tendo calcaneus and then runs

the lateral malleolus in company with the sural nerve. It fol

behind

dorsal venous arch of the foot (Fig. 10.19). It ascends

arises from the lateral part of the

small saphenous vein

The

Superficial Veins

the posteromedial surface of the leg (Fig. 10.1).

(see page 463), gives off branches that supply the skin on

a branch of the femoral nerve

saphenous nerve,

The

eral surface of the leg (Fig. 10.1).

479), supplies the skin on the lower part of the posterolat

a branch of the tibial nerve (see page

sural nerve,

The

(Fig. 10.1).

on the upper part of the posterolateral surface of the leg

common peroneal nerve (see page 479), supplies the skin

a branch of the

lateral cutaneous nerve of the calf,

The

of the back of the leg (Fig. 10.1).

supplies the skin over the popliteal fossa and the upper part

the back of the thigh (see page 465). In the popliteal fossa, it

of the thigh descends on

posterior cutaneous nerve

The

Cutaneous Nerves

of the little toe (see page 498).

cent sides of the first and second toes and the lateral side

dorsal surfaces of the skin of all the toes, except the adja

the dorsum of the foot. In addition, branches supply the

to the skin on the lower part of the front of the leg and

Medial and lateral branches are distributed

Cutaneous:

(Fig. 10.44)

branches to the peroneus longus and brevis

Muscular

Branches

cutaneous (Figs. 10.47 and 10.50).

brevis muscles, and in the lower part of the leg it becomes

and 10.50). It descends between the peroneus longus and

the lateral side of the neck of the fibula (Figs. 10.44, 10.46,

487

■

The Back of the Leg

Skin

■

Contents of the Posterior Fascial

Compartment of the Leg

■

fibers of the soleus or partial tearing of the tendo calcaneus is

gastrocnemius and soleus muscles retract proximally, leaving

tion. A sudden, sharp pain is felt, with immediate disability. The

Tearing of the gastrocnemius or soleus muscles will produce

Gastrocnemius and Soleus Muscle Tears

severe localized pain over the damaged muscle. Swelling may

be present.

Ruptured Tendo Calcaneus

Rupture of the tendo calcaneus is common in middle-aged

men and frequently occurs in tennis players. The rupture

occurs at its narrowest part, about 2 in. (5 cm) above its inser-

a palpable gap in the tendon. It is impossible for the patient to

actively plantar flex the foot. The tendon should be sutured as

soon as possible and the leg immobilized with the ankle joint

plantar flexed and the knee joint flexed.

Rupture of the Plantaris Tendon

Rupture of the plantaris tendon is rare, although tearing of the

frequently diagnosed as such a rupture.

Plantaris Tendon and Autografts

The plantaris muscle, which is often missing, can be used for

tendon autografts in repairing severed flexor tendons to the

fingers; the tendon of the palmaris longus muscle can also be

used for this purpose.

C L I N I C A L N O T E S