The neck pdf - Head and Neck

Basic Anatomy

585

unilateral cleft lip

bilateral cleft lip

median cleft upper lip

median cleft lower lip

oblique facial cleft

FIGURE 11.44

Various forms of cleft lip.

FIGURE 11.45

Unilateral cleft upper lip. (Courtesy of

R. Chase.)

FIGURE 11.46

Bilateral cleft upper lip and palate. (Courtesy

of R. Chase.)

FIGURE 11.47

Right-sided oblique facial cleft and left-sided

cleft upper lip. There also is total bilateral cleft palate.

(Courtesy of R. Chase.)

clinically because an incision along a cleavage line will heal

run almost horizontally around the neck. This is important

The natural lines of cleavage of the skin are constant and

the deep cervical lymph nodes (Fig. 11.49).

carotid arteries, internal jugular veins, the vagus nerve, and

At the sides of these structures are the vertically running

of the alimentary system, the pharynx and the esophagus.

namely, the larynx and the trachea, and behind are parts

tral region of the neck are parts of the respiratory system,

a smaller group of flexor muscles (Fig. 11.49). In the cen

the vertebrae is a mass of extensor muscles and in front is

which is convex forward and supports the skull. Behind

strengthened by the cervical part of the vertebral column,

nal notch and the upper border of the clavicle below. It is

lower margin of the mandible above and the supraster

The neck is the region of the body that lies between the

The Neck

Skin of the Neck

586

CHAPTER 11

The Head and Neck

FIGURE 11.48

Cleft lip and palate.

351;8:769.)

of age, after synchronous nasolabial repair and palatal closure performed at a second stage. (Courtesy of Dr. J. B. Mulliken.

Shows the same child at 18 months

An infant with bilateral complete cleft lip and palate.

(Courtesy of Dr. B. Benacerraf.)

A three-dimensional ultrasonograph reveals bilateral cleft lip at 22 weeks of gestation.

N Engl J Med

pretracheal fascia

trachea

esophagus

thyroid gland

carotid sheath

internal

jugular vein

deep cervical

lymph node

common

carotid artery

vagus nerve

sympathetic

trunk

investing

layer of

fascia

prevertebral

layer of fascia

vertebral artery

spinal nerve

ligamentum nuchae

semispinalis capitis

splenius capitis

levator scapulae muscle

trapezius

spinal

part of

accessory

nerve

scalenus

medius

muscle

scalenus

muscle

longus cervicis

muscle

omohyoid muscle

platysma

sternothyroid muscle

sternohyoid muscle

sternocleidomastoid muscle

recurrent laryngeal nerve

FIGURE 11.49

vical vertebra.

Cross section of the neck at the level of the 6th cer

Basic Anatomy

the posterior border of the sternocleidomastoid muscle

of the cervical plexus. The branches emerge from beneath

by anterior rami of cervical nerves 2 to 4 through branches

The skin of the front and sides of the neck is supplied

cervical nerve has no cutaneous branch.

of the posterior ramus of the 2nd cervical nerve. The 1st

is a branch

greater occipital nerve

2 to 5 (Fig. 11.50). The

supplied segmentally by posterior rami of cervical nerves

neck and on the back of the scalp as high as the vertex is

The skin overlying the trapezius muscle on the back of the

Cutaneous Nerves

as a wide or heaped-up scar.

as a narrow scar, whereas one that crosses the lines will heal

587

(Fig. 11.50).

sternocleidomastoid muscle. It passes forward across

from behind the middle of the posterior border of the

(C2 and 3) emerges

transverse cutaneous nerve

The

cle (Fig. 11.50).

dible, the parotid gland, and on both surfaces of the auri

branches that supply the skin over the angle of the man

across the sternocleidomastoid muscle and divides into

(C2 and 3) ascends

great auricular nerve

The

the auricle (Fig. 11.50).

eral part of the occipital region and the medial surface of

sternocleidomastoid muscle to supply the skin over the lat

sory nerve and ascends along the posterior border of the

(C2) hooks around the acces

lesser occipital nerve

The

-
-

that muscle and divides into branches that

supply

greater
occipital
nerve
(C2)
lesser
occipital
nerve

posterior
rami of
C3, 4,
and 5

supraclavicular nerves
(C3 and 4)

transverse cutaneous nerve
of neck (C2 and 3)

great auricular nerve
(C2 and 3)

mental nerve

buccal nerve

infraorbital nerve

external nasal
nerve

zygomaticofacial
nerve

lacrimal nerve

supratrochlear nerve

zygomaticotemporal
nerve

supraorbital nerve

auriculotemporal
nerve

FIGURE 11.50

Sensory nerve supply to skin of the head

neck, from the body of the mandible to the sternum

the skin on the anterior and lateral surfaces of the

branches of the trigeminal nerve.

supplied by the great auricular nerve (C2 and 3) and not by

and neck. Note that the skin over the angle of the jaw is

(Fig. 11.50).

Anterior jugular vein

Suprascapular vein

Transverse cervical vein

external jugular vein about halfway along its course

the posterior part of the scalp and neck and joins the

Posterior external jugular vein, a small vein that drains

Posterior division of the retromandibular vein

Posterior auricular vein

tributaries:

The external jugular vein (Fig. 11.52) has the following

Tributaries

dle of the clavicle.

course extends from the angle of the mandible to the mid

vian vein (Fig. 11.53). It varies considerably in size, and its

triangle, pierces the deep fascia and drains into the subcla

mastoid muscle and, just above the clavicle in the posterior

(Fig. 11.52). It descends obliquely across the sternocleido

with the posterior division of the retromandibular vein

the mandible by the union of the posterior auricular vein

The external jugular vein begins just behind the angle of

External Jugular Vein

Superficial Veins

the superficial fascia. It is described in Table 11.5, page

but clinically important muscular sheet embedded in

The platysma muscle (Figs. 11.38 and 11.51) is a thin

nodes.

tion, the superficial veins, and the superficial lymph

the cutaneous nerves referred to in the previous sec

encloses the platysma muscle. Also embedded in it are

The superficial fascia of the neck forms a thin layer that

spine of the scapula.

the posterior aspect of the shoulder as far down as the

upper half of the deltoid muscle; this nerve also supplies

clavicle and supplies the skin over the shoulder and the

crosses the lateral end of the

eral supraclavicular nerve

clavicle and supplies the skin of the chest wall. The

crosses the middle of the

mediate supraclavicular nerve

inter

supplies the skin as far as the median plane. The

crosses the medial end of the clavicle and

vicular nerve

medial supracla

level of the second rib (Fig. 11.50). The

onto the chest wall and shoulder region, down to the

muscle and descend across the side of the neck. They pass

beneath the posterior border of the sternocleidomastoid

(C3 and 4) emerge from

supraclavicular nerves

The

lat-

Superficial Fascia

Platysma

589.

■

588

CHAPTER 11

The Head and Neck

Visibility of the External Jugular Vein

the cricoid cartilage and the clavicle. The passage of the catheter

The vein is catheterized about halfway between the level of

one third of the way up the neck. As the patient sits up, the blood

even when they are asked to hold their breath, which impedes the

sue of men. In obese individuals, the vein may be difficult to identify

The external jugular vein is less obvious in children and women

because their subcutaneous tissue tends to be thicker than the tis-

venous return to the right side of the heart and distends the vein.

The superficial veins of the neck tend to be enlarged and

often tortuous in professional singers because of prolonged

periods of raised intrathoracic pressure.

The External Jugular Vein as a Venous Manometer

The external jugular vein serves as a useful venous manometer.

Normally, when the patient is lying at a horizontal angle of 30°,

the level of the blood in the external jugular veins reaches about

level falls until it is no longer visible behind the clavicle.

External Jugular Vein Catheterization

The external jugular vein can be used for catheterization, but the

presence of valves or tortuosity may make the passage of the

catheter difficult. Because the right external jugular vein is in the

most direct line with the superior vena cava, it is the one most

commonly used (Fig. 11.54).

should be performed during inspiration when the valves are open.

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

platysma

hyoid bone

thyroid cartilage

anterior belly
of the omohyoid

sternohyoid

anterior jugular
vein

jugular arch

reflected skin

common

carotid

artery

internal

jugular

vein

sternocleido-

mastoid

isthmus of

thyroid gland

trachea

FIGURE 11.51

sma muscles and the lower ends of the

Dissection of the anterior aspect of the neck showing the platy

sternocleidomastoid muscles on both sides. The skin has been reflected downward.

Basic Anatomy

589

Muscles of the Neck

T A B L E 1 1 . 5

Two muscles acting

Muscle

Origin

Insertion

Nerve Supply

Action

Platysma

Deep fascia over

pectoralis major and

deltoid

Body of mandible and angle

of mouth

Facial nerve cervical

branch

Depresses mandible and

angle of mouth

Sternocleidomastoid

Manubrium sterni and

medial third of clavicle

Mastoid process of

temporal bone and

occipital bone

Spinal part of

accessory nerve

and C2 and 3

together extend head

and flex neck; one

muscle rotates head to

opposite side

Digastric
Posterior belly

Mastoid process of

temporal bone

Intermediate tendon is held

to hyoid by fascial sling

Facial nerve

Depresses mandible or

elevates hyoid bone

Anterior belly

Body of mandible

Nerve to mylohyoid

Stylohyoid

Styloid process

Body of hyoid bone

Facial nerve

Elevates hyoid bone

Mylohyoid

Mylohyoid line of body of

mandible

Body of hyoid bone and

fibrous raphe

Inferior alveolar

nerve

Elevates floor of mouth

and hyoid bone or

depresses mandible

Geniohyoid

Inferior mental spine of

mandible

Body of hyoid bone

1st cervical nerve

Elevates hyoid bone or

depresses mandible

Sternohyoid

Manubrium sterni and

clavicle

Body of hyoid bone

Ansa cervicalis; C1,

2, and 3

Depresses hyoid bone

Sternothyroid

Manubrium sterni

Oblique line on lamina of

thyroid cartilage

Ansa cervicalis; C1,

2, and 3

Depresses larynx

Thyrohyoid

Oblique line on lamina of

thyroid cartilage

Lower border of body of

hyoid bone

1st cervical nerve

Depresses hyoid bone or

elevates larynx

Omohyoid
Inferior belly

Upper margin of scapula

and suprascapular

ligament

Intermediate tendon is held

to clavicle and first rib by

fascial sling

Ansa cervicalis; C1,

2, and 3

Depresses hyoid bone

Superior belly

Lower border of body of

hyoid bone

Transverse processes

Transverse processes of

Scalenus anterior

3rd, 4th, 5th, and 6th

cervical vertebrae

1st rib

C4, 5, and 6

Elevates 1st rib; laterally

flexes and rotates

cervical part of

vertebral column

Scalenus medius

of upper six cervical

vertebrae

1st rib

Anterior rami of

cervical nerves

Elevates 1st rib; laterally

flexes and rotates

cervical part of

vertebral column

Scalenus posterior

of lower cervical

vertebrae

2nd rib

Anterior rami of

cervical nerves

Elevates 2nd rib; laterally

flexes and rotates

cervical part of

vertebral column

590

CHAPTER 11

oid ligament and to the thyroid cartilage by the thyrohyoid

cornua (Fig. 11.32). It is attached to the skull by the stylohy

shaped and consists of a body and two greater and two lesser

not articulate with any other bones. The hyoid bone is U

of the neck below the mandible and abides the larynx. It does

The hyoid bone is a mobile single bone found in the midline

page 686.

The cervical part of the vertebral column is described on

Cervical Vertebrae

deep cervical lymph nodes.

and mastoid lymph nodes (see page 604) and drain into the

(Fig. 11.40). They receive lymph vessels from the occipital

jugular vein superficial to the sternocleidomastoid muscle

The superficial cervical lymph nodes lie along the external

Superficial Lymph Nodes

drain into the external jugular vein.

ally and passes deep to the sternocleidomastoid muscle to

. The vein then turns sharply later

jugular arch

called the

the veins of the two sides are united by a transverse trunk

The Head and Neck

Bones of the Neck

Hyoid Bone

posterior auricular
vein

posterior external
jugular vein
external jugular vein

transverse
cervical vein

suprascapular vein

jugular arch

anterior jugular
vein

facial
vein

retromandibular vein

FIGURE 11.52

Major superficial veins of the face and neck.

greater occipital nerve

occipital artery

sternocleidomastoid

lesser occipital nerve

semispinalis capitis

posterior ramus C3

trapezius

splenius capitis

great auricular nerve

posterior ramus C4

levator scapulae

C3 and C4

spinal part of accessory nerve

posterior ramus C5

scalenus medius

superficial cervical artery

clavicle

suprascapular nerve and artery

external jugular vein
third part of subclavian artery

nerve to subclavius

lower trunk of brachial plexus

sternocleidomastoid

inferior belly of omohyoid

middle trunk of brachial plexus

upper trunk of brachial plexus

dorsal scapular nerve

supraclavicular nerves

superior belly of omohyoid

transverse cutaneous nerve

FIGURE 11.53

Posterior triangle of the neck.

neck close to the midline. Just above the suprasternal notch,

union of several small veins (Fig. 11.52). It runs down the

The anterior jugular vein begins just below the chin, by the

Anterior Jugular Vein

Basic Anatomy

591

angle of
mandible

external
jugular
vein

midpoint of clavicle

skin

platysma

external
jugular
vein

catheter

trapezius

investing
layer of
deep
cervical
fascia

sternocleidomastoid
muscle

superior vena cava

right brachiocephalic vein

right subclavian
vein

external
jugular
vein

catheter

FIGURE 11.54

Catheterization of the right external jugular vein.

membrane. The hyoid bone forms a base for the tongue and

of the external jugular vein as it crosses the posterior triangle of the neck.

Cross section of the neck showing the relationships

how the external jugular vein joins the subclavian vein at a right angle.

Surface marking of the vein.

B. Site of catheterization. Note

is suspended in position by muscles that

t it to the

connec

muscles are also described in Table 11.5.

infrahyoid muscles and the anterior and lateral vertebral

and 11.51) are described in Table 11.5. The suprahyoid and

The superficial muscles of the side of the neck (Figs. 11.38

shown in Figure 11.32.

The important muscles attached to the hyoid bone are

thyroid cartilage, to the sternum, and to the scapula.

mandible, to the styloid process of the temporal bone, to the

Muscles of the Neck

fully sutured, since the tone of the platysma can pull on the

In lacerations or surgical incisions in the neck, it is very impor

firmly. The muscle extends from the body of the mandible

Clinical Identification of the Platysma

The platysma can be seen as a thin sheet of muscle just

beneath the skin by having the patient clench his or her jaws

downward over the clavicle onto the anterior chest wall.

Platysma Tone and Neck Incisions

tant that the subcutaneous layer with the platysma be care-

scar tissue, resulting in broad, unsightly scars.

Platysma Innervation, Mouth Distortion, and Neck

Incisions

The platysma muscle is innervated by the cervical branch of

the facial nerve. This nerve emerges from the lower end of

the parotid gland and travels forward to the platysma; it then

sometimes crosses the lower border of the mandible to supply

the depressor anguli oris muscle (see page XXX). Skin lacera-

tions over the mandible or upper part of the neck may distort

the shape of the mouth.

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

Key Neck Muscles

sternocleidomastoid muscle are summarized in Table 11.5.

plexus. The origin, insertion, nerve supply, and action of the

nerves, the phrenic nerve, and the upper part of the brachial

of the posterior border is related to the cervical plexus of

sma muscle, and the external jugular vein. The deep surface

The muscle is covered superficially by skin, fascia, the platy

deep cervical lymph nodes; it also overlaps the thyroid gland.

covers the carotid arteries, the internal jugular vein, and the

rior and posterior triangles (Fig. 11.56). The anterior border

mastoid process of the skull. It divides the neck into ante

the side of the neck from the sternoclavicular joint to the

and 11.55) contracts, it appears as an oblique band crossing

When the sternocleidomastoid muscle (Figs. 11.51, 11.53,

Sternocleidomastoid Muscle

Sternocleidomastoid Muscle and Protection from

and the greater part of the sternocleidomastoid muscles have

with the head and neck fully extended, some individuals have

The sternocleidomastoid, a strong, thick muscle crossing the

Trauma

side of the neck, protects the underlying soft structures from

blunt trauma. Suicide attempts by cutting one’s throat often

fail because the individual first extends the neck before mak-

ing several horizontal cuts with a knife. Extension of the cer-

vical part of the vertebral column and extension of the head

at the atlantooccipital joint cause the carotid sheath with its

contained large blood vessels to slide posteriorly beneath the

sternocleidomastoid muscle. To achieve the desired result

to make several attempts and only succeed when the larynx

been severed. The common sites for the wounds are immedi-

ately above and below the hyoid bone.

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

(continued)

592

CHAPTER 11

The Head and Neck

Congenital Torticollis

medial border is related to the thoracic duct.

the sympathetic trunk (Fig. 11.57). On the left side, the

Related to the vertebral artery and vein and

Medially:

scalenus anterior muscle.

(Fig. 11.57). The scalenus medius muscle lies behind the

chial plexus, and the second part of the subclavian artery

Related to the pleura, the origin of the bra

Posteriorly:

muscle.

of deep cervical fascia bind the phrenic nerve to the

and suprascapular arteries and the prevertebral layer

cal lymph nodes (Fig. 11.49). The transverse cervical

nerve, the internal jugular vein, and the deep cervi

Related to the carotid arteries, the vagus

Anteriorly:

Important Relations

to the 1st rib.

and it descends almost vertically from the vertebral column

standing the root of the neck (Fig. 11.57). It is deeply placed

The scalenus anterior muscle is a key muscle in under

Scalenus Anterior Muscle

upward to the opposite side. If left untreated, asymmetrical

cess is thus pulled down toward the sternoclavicular joint of

Most cases of congenital torticollis are a result of excessive

stretching of the sternocleidomastoid muscle during a dif-

ficult labor. Hemorrhage occurs into the muscle and may be

detected as a small, rounded “tumor” during the early weeks

after birth. Later, this becomes invaded by fibrous tissue,

which contracts and shortens the muscle. The mastoid pro-

the same side, the cervical spine is flexed, and the face looks

growth changes occur in the face, and the cervical vertebrae

may become wedge shaped.

Spasmodic Torticollis

Spasmodic torticollis, which results from repeated chronic

contractions of the sternocleidomastoid and trapezius mus-

cles, is usually psychogenic in origin. Section of the spinal part

of the accessory nerve may be necessary in severe cases.

■

sternocleidomastoid

internal jugular vein

occipital artery

hypoglossal nerve

descending branch

of hypoglossal nerve

internal carotid artery

superior laryngeal nerve

deep cervical lymph nodes

descending cervical nerve

thyrohyoid

ansa cervicalis

spinal part of

accessory nerve

common

carotid

artery

external jugular vein

sternothyroid

anterior jugular vein

isthmus of thyroid gland

superior belly of omohyoid

cricoid cartilage

thyroid cartilage

external laryngeal nerve

superior thyroid artery

internal laryngeal nerve

sternohyoid

nerve to thyrohyoid

mylohyoid

anterior belly

of digastric

stylohyoid

lingual

artery

facial artery

posterior auricular

artery

external carotid artery

maxillary artery

superficial temporal artery

posterior belly of digastric

superior thyroid

vein

FIGURE 11.55

Anterior triangle of the neck.

Basic Anatomy

593

submental triangle

lower margin of body of mandible

of digastric

posterior belly

digastric triangle

of digastric

anterior belly

carotid triangle

muscular triangle

superior belly of omoh

sternoh

sternothyroid

sternocleidomastoid

sternal head of

scalenus anterior

(supraclavicular triangle)

posterior triangle

clavicle

omohyoid

inferior belly of

(occipital triangle)

posterior triangle

levator scapulae

sternocleidomastoid

semispinalis capitis

splenius capitis

trapezius

scalenus medius

yoid

hyoid bone

mylohyoid

FIGURE 11.56

Muscular triangles of the neck.

agus and in front of the prevertebral muscles and the

tum across the neck behind the pharynx and the esoph

The prevertebral layer is a thick layer that passes like a sep

Prevertebral Layer

and encloses the infrahyoid muscles.

roid and the parathyroid glands, forming a sheath for them,

to the laryngeal cartilages (Fig. 11.49). It surrounds the thy

The pretracheal layer is a thin layer that is attached above

Pretracheal Layer

muscles (Fig. 11.49).

splits to enclose the trapezius and the sternocleidomastoid

The investing layer is a thick layer that encircles the neck. It

Investing Layer

It is also condensed to form the carotid sheath (Fig. 11.49).

prevertebral layer.

pretracheal layer,

ing layer,

invest

densed to form well-defined, fibrous sheets called the

the viscera of the neck (Fig. 11.49). In certain areas, it is con

The deep cervical fascia supports the muscles, the vessels, and

nus anterior muscle are summarized in Table 11.5.

The origin, insertion, nerve supply, and action of the scale

part of the subclavian artery (Fig. 11.57).

cal plexus, the roots of the brachial plexus, and the third

Related to the emerging branches of the cervi

Laterally:

■

Deep Cervical Fascia

the

and the

-
-

vertebral column (Fig. 11.49). It forms the fascial floor of

bral, the pretracheal, and the investing layers of the deep

The carotid sheath is a local condensation of the preverte

Carotid Sheath

(see page 596).

axillary sheath

rib into the axilla to form the important

the posterior triangle, and it extends laterally over the first

594

CHAPTER 11

The Head and Neck

levator scapulae

lesser occipital nerve

great auricular nerve

transverse cutaneous nerve

supraclavicular nerves

middle cervical

sympathetic ganglion

upper trunk of

brachial plexus

inferior cervical

sympathetic ganglion

ansa subclavia

costocervical trunk

vertebral artery

cervical pleura

right recurrent

laryngeal nerve

phrenic nerve

right brachiocephalic vein

vagus

sternohyoid

sternothyroid

trachea

left recurrent laryngeal nerve

internal jugular vein

internal thoracic artery

subclavian vein

external jugular vein

third part of
subclavian artery

scalenus anterior

suprascapular artery

thyrocervical trunk

superficial cervical artery

thoracic duct

upper trunk of brachial plexus

inferior thyroid artery

esophagus

phrenic nerve

longus cervicis

scalenus medius

vertebral artery

transverse process of atlas

mastoid process

longus capitis

basilar part of occipital bone

FIGURE 11.57

Prevertebral region and the root of the neck.

Basic Anatomy

595

Clinical Significance of the Deep Fascia of the Neck

abscess but must not forget the existence of the deeply placed

Later, this becomes eroded at one point, and the pus passes into

ward and upward. Further spread downward may involve the

most commonly involve the lower molar teeth.

Dental infections

and the tough fascia can determine the direction of spread of

esophagus can spread among the fascial planes and spaces,

ically important. Among the more important spaces are the vis

As previously described, the deep fascia in certain areas forms

distinct sheets called the investing, pretracheal, and preverte-
bral layers. These fascial layers are easily recognizable to the

surgeon at operation.

Fascial Spaces
Between the more dense layers of deep fascia in the neck is

loose connective tissue that forms potential spaces that are clin-

ceral, retropharyngeal, submandibular, and masticatory spaces

(Fig. 11.58).

The deep fascia and the fascial spaces are important

because organisms originating in the mouth, teeth, pharynx, and

infection and the path taken by pus. It is possible for blood, pus,

or air in the retropharyngeal space to spread downward into the

superior mediastinum of the thorax.

Acute Infections of the Fascial Spaces of the Neck

The infection spreads medially from the mandible into the sub-

mandibular and masticatory spaces and pushes the tongue for-

visceral space and lead to edema of the vocal cords and airway

obstruction.

Ludwig’s angina is an acute infection of the submandibular

fascial space and is commonly secondary to dental infection.

Chronic Infection of the Fascial Spaces of the Neck
Tuberculous infection of the deep cervical lymph nodes can

result in liquefaction and destruction of one or more of the nodes.

The pus is at first limited by the investing layer of the deep fascia.

the less restricted superficial fascia. A dumbbell or collar-stud

abscess is now present. The clinician is aware of the superficial

abscess.

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

trachea

thyroid gland

visceral space

pretracheal layer of
deep cervical fascia

sternohyoid
muscle

superior belly of omohyoid muscle

sternothyroid

sternocleidomastoid
muscle

carotid sheath

esophagus

retropharyngeal space

prevertebral layer of
deep cervical fascia

pretracheal layer
of deep cervical fascia

submandibular
space

mylohyoid muscle

medial

pterygoid

muscle
masticatory
space

investing layer of
deep cervical fascia

mandible

masseter muscle

zygomatic arch

temporalis

FIGURE 11.58

the masticatory space.

Vertical section of the body of the mandible close to the angle showing

of the retropharyngeal and submandibular spaces.

Sagittal section of the neck showing the positions

Cross section of the neck showing the visceral space. B.

596

CHAPTER 11

(Figs. 11.55 and 11.60).

divides into the external and internal carotid arteries

to the upper border of the thyroid cartilage. Here, it

nocleidomastoid muscle, from the sternoclavicular joint

the neck under cover of the anterior border of the ster

95). The common carotid artery runs upward through

arch of the aorta in the superior mediastinum (see page

(Figs. 11.57 and 11.59). The left artery arises from the

ocephalic artery behind the right sternoclavicular joint

The right common carotid artery arises from the brachi

Common Carotid Artery

and lateral vertebral muscles are described in Table 11.5.

The suprahyoid and infrahyoid muscles and the anterior

below (Fig. 11.56).

supraclavicular triangle

and a small

above

occipital triangle

into a large

of the omohyoid muscle

inferior belly

angle of the neck is further subdivided by the

and inferiorly by the clavicle (Fig. 11.56). The posterior tri

zius muscle, anteriorly by the sternocleidomastoid muscle,

The posterior triangle is bounded posteriorly by the trape

Posterior Triangle

(Fig. 11.56).

muscular triangle

submental triangle,

the

digastric triangle,

carotid triangle,

divided into the

and anteriorly by the midline (Fig. 11.56). It is further sub

mandible, posteriorly by the sternocleidomastoid muscle,

The anterior triangle is bounded above by the body of the

Anterior Triangle

anterior and the posterior triangles (Fig. 11.56).

The sternocleidomastoid muscle divides the neck into the

Muscular Triangles of the Neck

(Fig. 11.80).

to the superior constrictor and the buccinator muscles

the mylohyoid line of the mandible. It gives attachment

cess of the medial pterygoid plate to the posterior end of

Connects the hamular pro

Pterygomandibular ligament:

sphenoid bone to the lingula of the mandible (Fig. 11.33)

Connects the spine of the

Sphenomandibular ligament:

to the angle of the mandible (Fig. 11.33)

Connects the styloid process

Stylomandibular ligament:

lesser cornu of the hyoid bone (Fig. 11.80)

Connects the styloid process to the

Stylohyoid ligament:

Cervical Ligaments

axillary sheath.

extends into the axilla and is called the

muscles, they carry with them a sheath of the fascia, which

val between the scalenus anterior and the scalenus medius

clavian artery and the brachial plexus emerge in the inter

muscles lie at first deep to the prevertebral fascia. As the sub

interval between the scalenus anterior and scalenus medius

All the anterior rami of the cervical nerves that emerge in the

deep cervical lymph nodes (Fig. 11.49).

arteries, the internal jugular vein, the vagus nerve, and the

fascia that surround the common and internal carotid

The Head and Neck

Axillary Sheath

-
-

the

and the

Arteries of the Head and Neck

posterior
auricular
artery

occipital artery

internal
carotid artery

carotid sinus

vertebral
artery

subclavian artery

common carotid artery

superior thyroid artery

lingual artery

facial
artery

maxillary
artery

superficial
temporal
artery

external carotid artery

FIGURE 11.59

Main arteries of the head and neck. Note that

the heart rate and vasodilatation of the arterioles.

tor mechanism: A rise in blood pressure causes a slowing of

geal nerve. The carotid sinus serves as a reflex pressorecep

numerous nerve endings derived from the glossopharyn

elsewhere, but the adventitia is relatively thick and contains

(Fig. 11.60). The tunica media of the sinus is thinner than

carotid sinus

artery shows a localized dilatation, called the

carotid artery or the beginning of the internal carotid

At its point of division, the terminal part of the common

Carotid Sinus

artery—are not shown.

and the internal thoracic artery—branches of the subclavian

for clarity the thyrocervical trunk, the costocervical trunk,

-
-

rate, a fall in blood pressure, and cerebral ischemia with fainting.

both carotid sinuses can cause excessive slowing of the heart

In cases of carotid sinus hypersensitivity, pressure on one or

Carotid Sinus Hypersensitivity

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

Carotid Body

vagus nerve (Fig. 11.49).

course and is closely related to the internal jugular vein and

tive tissue sheath, called the carotid sheath, throughout its

The common carotid artery is embedded in a connec

tory movements.

blood pressure and heart rate and an increase in respira

in the blood. Such a stimulus reflexly produces a rise in

tive to excess carbon dioxide and reduced oxygen tension

nerve. The carotid body is a chemoreceptor, being sensi

(Fig. 11.60). It is innervated by the glossopharyngeal

to the point of bifurcation of the common carotid artery

The carotid body is a small structure that lies posterior

Basic Anatomy

597

cervical

external auditory meatus

mastoid process

superior

ganglion

of vagus

superior

sympathetic

ganglion

spinal part of

accessory nerve
cranial part of

accessory nerve

internal jugular

vein

inferior

ganglion

of vagus

vagus nerve

middle cervical

ganglion

carotid body

subclavian artery

stellate ganglion

ansa subclavia

common carotid artery

descending cervical nerve (C2 and 3)

ansa cervicalis

descending branch of

hypoglossal nerve (C1)

stylopharyngeus

carotid sinus

superior thyroid artery

internal laryngeal nerve

external laryngeal nerve

nerve to thyrohyoid

lingual artery

hypoglossal nerve

pharyngeal branch of vagus nerve

glossopharyngeal nerve

facial artery

stylohyoid

styloglossus

maxillary artery

superficial temporal artery

internal carotid artery

styloid process

FIGURE 11.60

Styloid muscles, vessels, and nerves of the neck.

artery gives off no branches.

Apart from the two terminal branches, the common carotid

Branches of the Common Carotid Artery

ally, the vagus nerve (Fig. 11.49).

The internal jugular vein and, posterolater

Laterally:

roid gland also lies medially.

trachea and esophagus (Fig. 11.49). The lobe of the thy

The larynx and pharynx and, below these, the

Medially:

neck are the vertebral vessels.

sympathetic trunk (Fig. 11.57). In the lower part of the

cervical vertebrae, the prevertebral muscles, and the

The transverse processes of the lower four

Posteriorly:

superior belly of the omohyoid (Fig. 11.55)

mastoid, the sternohyoid, the sternothyroid, and the

The skin, the fascia, the sternocleido

Anterolaterally:

Relations of the Common Carotid Artery

■

Taking the Carotid Pulse

The bifurcation of the common carotid artery into the inter-

nal and external carotid arteries can be easily palpated just

beneath the anterior border of the sternocleidomastoid mus-

cle at the level of the superior border of the thyroid cartilage.

This is a convenient site to take the carotid pulse.

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

External Carotid Artery

tures in the neck, face, and scalp; it also supplies the tongue

of the common carotid artery (Fig. 11.59). It supplies struc

The external carotid artery is one of the terminal branches

598

CHAPTER 11

The internal carotid artery leaves the neck by passing into

gland (Figs. 11.60 and 11.85B).

lies superficially; it then passes deep to the parotid salivary

with the internal jugular vein and vagus nerve. At first it

artery ascends in the neck embedded in the carotid sheath

the brain, the eye, the forehead, and part of the nose. The

the thyroid cartilage (Figs. 11.55 and 11.59). It supplies

common carotid artery at the level of the upper border of

The internal carotid artery begins at the bifurcation of the

Internal Carotid Artery

nal carotid artery are shown in Figure 11.59.

The origin and distribution of the branches of the exter

where it is prone to damage after a blow to the head.

skull and the thin anteroinferior angle of the parietal bone,

upper part of the greater wing of the sphenoid bone of the

Accompanied by its vein, it grooves (or tunnels) through the

it lies close to the motor area of the cerebral cortex of the brain.

11.20 and 11.131). The anterior branch is important because

skull and divides into anterior and posterior branches (Figs.

foramen spinosum (Fig. 11.66). It runs laterally within the

The middle meningeal artery enters the skull through the

Middle Meningeal Artery

inside the skull.

cles of mastication, the nose, the palate, and the meninges

Branches supply the upper and the lower jaws, the mus

Branches of the Maxillary Artery

of the skull.

mandible (Fig. 11.59) and enters the pterygopalatine fossa

The maxillary artery runs forward medial to the neck of the

Maxillary Artery

nerve, and it supplies the scalp.

(Fig. 11.59). It is accompanied by the auriculotemporal

arch, where it may be palpated just in front of the auricle

The superficial temporal artery ascends over the zygomatic

Superficial Temporal Artery

scalp (Fig. 11.59).

The posterior auricular artery supplies the auricle and the

Posterior Auricular Artery

The artery supplies the back of the scalp (Fig. 11.59).

Occipital Artery

the face.

mandibular salivary gland, and the muscles and the skin of

supply the tonsil, the sub

Branches of the facial artery

terminates at the medial angle of the eye (Figs. 11.55 and

then ascends around the lateral margin of the mouth and

to the anterior border of the masseter muscle. The artery

border of the mandible. It then ascends over the face close

lar salivary gland and emerges and bends around the lower

the pharynx and the tonsil. It lies deep to the submandibu

The facial artery loops upward close to the outer surface of

Facial Artery

the tongue (Figs. 11.55 and 11.60).

The lingual artery loops upward and forward and supplies

Lingual Artery

plies the pharyngeal wall.

The ascending pharyngeal artery ascends along and sup

Ascending Pharyngeal Artery

plies the cricothyroid muscle.

accompanied by the external laryngeal nerve, which sup

pole of the thyroid gland (Figs. 11.55 and 11.60). It is

The superior thyroid artery curves downward to the upper

Superior Thyroid Artery

Maxillary artery

Superficial temporal artery

Posterior auricular artery

Occipital artery

Facial artery

Lingual artery

Ascending pharyngeal artery

Superior thyroid artery

Branches of the External Carotid Artery

gland, see Figure 11.85B.

For the relations of the external carotid artery in the parotid

arteries (Fig. 11.60).

vagus pass between the external and internal carotid

sopharyngeal nerve, and the pharyngeal branch of the

carotid artery. The stylopharyngeus muscle, the glos

The wall of the pharynx and the internal

Medially:

artery and then posterior to it.

11.85). The internal jugular vein first lies lateral to the

the parotid gland, it is crossed by the facial nerve (Fig.

digastric muscle, and the stylohyoid muscles. Within

hypoglossal nerve (Fig. 11.55), the posterior belly of the

being covered by skin and fascia. It is crossed by the

Above this level, the artery is comparatively superficial,

ning by the anterior border of the sternocleidomastoid.

The artery is overlapped at its begin

Anterolaterally:

Relations of the External Carotid Artery

the stylohyoid (Fig. 11.55).

to it. It is crossed by the posterior belly of the digastric and

but as it ascends in the neck, it passes backward and lateral

be felt. At first, it lies medial to the internal carotid artery,

of the sternocleidomastoid muscle, where its pulsations can

Close to its origin, the artery emerges from undercover

arteries.

ble by dividing into the superficial temporal and maxillary

stance of the parotid gland behind the neck of the mandi

border of the thyroid cartilage and terminates in the sub

and the maxilla. The artery begins at the level of the upper

The Head and Neck

-
-

■

11.59).

sphenoid bone. The internal carotid artery then inclines

upward again medial to the anterior clinoid process of the

cating with it). The artery then leaves the sinus and passes

ward in the cavernous venous sinus (without communi

part of the temporal bone. It then passes upward and for

the cranial cavity through the carotid canal in the petrous

-
-

backward, lateral to the optic chiasma, and

es by

terminat

dividing into the anterior and the middle cerebral arteries.

Basic Anatomy

The internal jugular vein and the vagus nerve

Laterally:

geal nerve

The pharyngeal wall and the superior laryn

Medially:

the upper three cervical vertebrae

longus capitis muscle, and the transverse processes of

The sympathetic trunk (Fig. 11.60), the

Posteriorly:

artery (Figs. 11.60 and 11.85B).

the vagus, the parotid gland, and the external carotid

the glossopharyngeal nerve, the pharyngeal branch of

lie the stylohyoid muscle, the stylopharyngeus muscle,

Above the digastric

the hypoglossal nerve (Fig. 11.55).

cia, the anterior border of the sternocleidomastoid, and

lie the skin, the fas

Anterolaterally: Below the digastric

Relations of the Internal Carotid Artery in the Neck

599

■

neck can cause visual impairment or blindness in the eye

Extensive arteriosclerosis of the internal carotid artery in the

Arteriosclerosis of the Internal Carotid Artery

on the side of the lesion because of insufficient blood flow

through the retinal artery. Motor paralysis and sensory loss

may also occur on the opposite side of the body because of

insufficient blood flow through the middle cerebral artery.

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

Branches of the Internal Carotid Artery

off the vertebral artery, the thyrocervical trunk, and the

the scalenus anterior muscle (Fig. 11.57). This part gives

the origin of the subclavian artery to the medial border of

The first part of the subclavian artery extends from

First Part of the Subclavian Artery

artery on each side and divides it into three parts.

The scalenus anterior muscle passes anterior to the

clavian artery (Fig. 11.57).

arches laterally in a manner similar to that of the right sub

in the thorax. It ascends to the root of the neck and then

The left subclavian artery arises from the arch of the aorta

Left Subclavian Artery

the outer border of the 1st rib, it becomes the axillary artery.

and between the scalenus anterior and medius muscles. At

and 11.59). It arches upward and laterally over the pleura

artery, behind the right sternoclavicular joint (Figs. 11.57

The right subclavian artery arises from the brachiocephalic

Right Subclavian Artery

Subclavian Arteries

arise from the circle and supply the brain.

that contribute to the circle. Cortical and central branches

the junction of the two vertebral arteries) are all arteries

communicating, posterior cerebral, and basilar (formed by

ies and the two vertebral arteries (Fig. 11.15). The anterior

sis between the branches of the two internal carotid arter

543) at the base of the brain. It is formed by the anastomo

The circle of Willis lies in the subarachnoid space (see page

Circle of Willis

the internal capsule of the brain.

tral branches that supply central masses of gray matter and

the cerebral cortex except the leg area. It also gives off cen

middle cerebral artery thus supplies all the motor area of

which are supplied by the posterior cerebral artery). The

pole and inferolateral surface of the hemisphere (both of

supplied by the anterior cerebral artery) and the occipital

the narrow strip along the superolateral margin (which is

the entire lateral surface of the cerebral hemisphere except

ally in the lateral cerebral sulcus of the brain. It supplies

of the internal carotid artery (Fig. 11.15), and it runs later

The middle cerebral artery is the largest terminal branch

Middle Cerebral Artery

communicating artery.

anterior

joined to the artery of the opposite side by the

the superolateral surfaces of the cerebral hemisphere. It is

the corpus callosum of the brain to supply the medial and

between the cerebral hemispheres and then winds around

internal carotid artery (Fig. 11.15). It passes forward

The anterior cerebral artery is a terminal branch of the

Anterior Cerebral Artery

the posterior cerebral artery (Fig. 11.15).

The posterior communicating artery runs backward to join

Posterior Communicating Artery

artery is an end artery and the only blood supply to the retina.

optic nerve and runs forward to enter the eyeball. The central

it gives off the central artery of the retina, which enters the

forward into the orbital cavity through the optic canal, and

as it emerges from the cavernous sinus (Fig. 11.20). It passes

The ophthalmic artery arises from the internal carotid artery

Ophthalmic Artery

branches, however, are given off in the skull.

There are no branches in the neck. Many important

-
-

internal thoracic artery.

spinal, posterior inferior cerebellar, medullary arteries

Meningeal, anterior and posterior

Branches in the skull:

Spinal and muscular arteries

Branches in the neck:

surfaces of the occipital lobe.

ral lobe and the visual cortex on the lateral and the medial

cal branches supply the inferolateral surfaces of the tempo

curves laterally and backward around the midbrain. Corti

(Fig. 11.15)

posterior cerebral artery

On each side, the

into the two posterior cerebral arteries.

pons, the cerebellum, and the internal ear. It finally divides

the anterior surface of the pons. It gives off branches to the

(Fig. 11.15) ascends in a groove on

basilar artery

The

sel of the opposite side to form the basilar artery.

at the level of the lower border of the pons, it joins the ves

the anterior surface of the medulla oblongata of the brain

through the foramen magnum into the skull. On reaching

ally above the posterior arch of the atlas and then ascends

upper six cervical vertebrae (Fig. 11.57). It passes medi

through the foramina in the transverse processes of the

ascends in the neck

vertebral artery

The

Branches

-
-

600

CHAPTER 11

this part.

vical arteries, the suprascapular arteries, or both arise from

has no branches. Occasionally, however, the superficial cer

The third part of the subclavian artery usually

Branches

the brachial plexus.

in the root of the neck, it is closely related to the nerves of

der of the 1st rib, where it becomes the axillary artery. Here,

across the posterior triangle of the neck to the lateral bor

lateral border of the scalenus anterior muscle (Fig. 11.57)

The third part of the subclavian artery extends from the

Third Part of the Subclavian Artery

deep muscles of the neck.

which supplies the

deep cervical artery,

spaces, and the

which supplies the 1st and the 2nd intercostal

tal artery,

superior intercos

dome of the pleura and divides into the

runs backward over the

costocervical trunk

The

Branches

scalenus anterior muscle (Fig. 11.57).

The second part of the subclavian artery lies behind the

Second Part of the Subclavian Artery

the superior epigastric and the musculophrenic arteries.

to the sternum; in the 6th intercostal space, it divides into

(Fig. 11.57). It descends vertically one fingerbreadth lateral

behind the 1st costal cartilage and in front of the pleura

descends into the thorax

internal thoracic artery

The

back of the scapula (Fig. 11.57).

chial plexus and follows the suprascapular nerve onto the

runs laterally over the bra

suprascapular artery

The

crosses the brachial plexus (Fig. 11.57).

is a small branch that

superficial cervical artery

The

inferior parathyroid glands.

recurrent laryngeal nerve. It supplies the thyroid and the

face of the thyroid gland, where it is closely related to the

ascends to the posterior sur

inferior thyroid artery

The

terminal branches (Fig. 11.57).

is a short trunk that gives off three

thyrocervical trunk

The

The Head and Neck

pressure is of great help, and the artery is compressed against

the subclavian artery. The use of a blunt object to exert the

strong pressure downward and backward on the third part of

remember that the hemorrhage can be stopped by exerting

In severe traumatic accidents to the upper limb involving lac

Palpation and Compression of the Subclavian

Artery in Patients with Upper Limb Hemorrhage

eration of the brachial or axillary arteries, it is important to

the upper surface of the 1st rib.

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

Veins of the Head and Neck

external jugular vein.

branch, which joins the posterior auricular vein to form the

anterior branch, which joins the facial vein, and a posterior

On leaving the parotid salivary gland, it divides into an

superficial temporal and the maxillary veins (Fig. 11.39).

The retromandibular vein is formed by the union of the

Retromandibular Vein

retromandibular vein.

illary vein joins the superficial temporal vein to form the

from the pterygoid venous plexus (Fig. 11.39). The max

The maxillary vein is formed in the infratemporal fossa

Maxillary Vein

retromandibular vein.

salivary gland, where it joins the maxillary vein to form the

and the auriculotemporal nerve and then enters the parotid

scalp (Fig. 11.39). It follows the superficial temporal artery

The superficial temporal vein is formed on the side of the

Superficial Temporal Vein

drains into the internal jugular vein.

by the anterior division of the retromandibular vein, and

side of the mouth. It then crosses the mandible, is joined

the face with the facial artery and passes around the lateral

with the cavernous sinus. The facial vein descends down

(Fig. 11.39). It is connected through the ophthalmic veins

supratrochlear veins

the union of the supraorbital and

The facial vein is formed at the medial angle of the eye by

Facial Vein

Veins of the Face and the Neck

spread of infection).

to the venous sinuses (and are an important route for the

skull bones (Fig. 11.9). They connect the veins of the scalp

The emissary veins are valveless veins that pass through the

Emissary Veins

vault of the skull (Fig. 11.9).

The diploic veins occupy channels within the bones of the

Diploic Veins

are described on page 544.

and inferior petrosal sinuses (Fig. 11.9). All these sinuses

the occipital sinus, the cavernous sinuses, and the superior

straight sinus, the transverse sinuses, the sigmoid sinuses,

include the superior and inferior sagittal sinuses, the

bones, the orbit, and the internal ear. The venous sinuses

no valves. They receive tributaries from the brain, the skull

page 544). They have thick, fibrous walls, but they possess

the meningeal layer of the dura mater (Fig. 11.37A; see also

The venous sinuses are situated between the periosteal and

Venous Sinuses

neighboring venous sinuses.

and the veins of the brainstem, all of which drain into the

They consist of the cerebral veins, the cerebellar veins,

The veins of the brain are thin walled and have no valves.

Veins of the Brain

The veins of the scalp, face, and neck

emissary veins

The veins of the brain, venous sinuses, diploic veins, and

The veins of the head and neck may be divided into

■