Surface anatomy of the head and neck pdf - Head and Neck

662

CHAPTER 11

The Head and Neck

of the subclavian or internal jugular veins.

chiocephalic vein. It may, however, end in the terminal part

downward and drains into the beginning of the left bra

reaching the medial border of the scalenus anterior, it turns

bends laterally behind the carotid sheath (Fig. 11.57). On

transverse process of the seventh cervical vertebra. Here, it

margin of the esophagus until it reaches the level of the

the root of the neck, it continues to ascend along the left

passing upward along the left margin of the esophagus. At

the left. On reaching the superior mediastinum, it is found

through the posterior mediastinum, inclining gradually to

through the aortic opening in the diaphragm and ascends

of the cisterna chyli (see page XXX). It enters the thorax

The thoracic duct begins in the abdomen at the upper end

jugular vein to form the brachiocephalic vein.

medial border of the scalenus anterior, it joins the internal

rib as a continuation of the axillary vein (Fig. 11.57). At the

The subclavian vein begins at the outer border of the first

Subclavian Vein

been described on page 599.

The relations and branches of the subclavian arteries have

similar to that of the right subclavian artery (Fig. 11.57).

the root of the neck and then arches laterally in a manner

arises from the arch of the aorta in the thorax. It ascends to

rib it becomes the axillary artery. The left subclavian artery

The Thoracic Duct

extend up into the root of the neck on each side. Covered by

Pleura and Lung Injuries in the Root of the Neck

The cervical dome of the pleura and the apex of the lung

the suprapleural membrane, they lie behind the subclavian

artery. A penetrating wound above the medial end of the clav-

icle may involve the apex of the lung.

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

natomy

aphic

adiog

Radiographic Appearance of the

the choroid plexuses also become calcified frequently.

normal adults. It lies in the midline. The falx cerebri and

dition. The pineal gland, for example, is calcified in 50% of

structures may indirectly give evidence of a pathologic con

become calcified in the adult, and the displacement of such

mass. However, a few normal structures within the skull

muscles, tendons, and nerves blend into a homogeneous

centrates mainly on the bony structures because the brain,

Routine radiologic examination of the head and neck con

Head and Neck

scan (Figs. 11.125, 11.126, and 11.127).

matter in the brain, its use can be more revealing than a CT

it provides better differentiation between gray and white

lesions. MRI is absolutely safe to the patient, and because

MRI is also commonly used for detection of intracranial

ples of CT scans of the head can be seen in Figure 11.124.

lesions. It is safe and provides accurate information. Exam

CT is commonly used for the detection of intracranial

Computed Tomography Scans

be seen in Figures 11.120, 11.121, 11.122, and 11.123.

clots, or abscesses. Examples of cerebral arteriograms can

tion of space-occupying lesions such as tumors, blood

detect abnormalities of the cerebral arteries and localiza

The technique of cerebral arteriography can be used to

studied in Figures 11.116, 11.117, 11.118, and 11.119.

straight posteroanterior views and lateral views can be

The radiographic appearances of the skull as seen on

ods of studying the intracranial contents.

scans has provided physicians with safe and accurate meth

The introduction of CT and MRI

(cerebral arteriogram).

contrast media into the arterial system leading to the brain

The brain can be studied indirectly by the injection of

Radiographic Appearance of the

Skull

Cerebral Arteriography

Magnetic Resonance Imaging

natomy

face

Surface Landmarks of the Head

right and left cerebral hemispheres.

which separates the

longitudinal cerebral fissure,

superior sagittal sinus,

falx cerebri,

of the underlying

the superior aspect of the head would indicate the position

ing the nasion to the external occipital protuberance over

the spinous processes of the cervical vertebrae. A line join

runs down the back of the neck, connecting the skull to

to the ligamentum nuchae, which is a large ligament that

at the junction of the head and neck and gives attachment

part of the occipital bone (Fig. 11.128). It lies in the midline

This is a bony prominence in the middle of the squamous

the nose (Fig. 11.128).

The nasion is the depression in the midline at the root of

Nasion

External Occipital Protuberance

the

and the

Surface Anatomy

Tympanic Membrane

pulled straight back or downward and backward.

cle upward and backward. In small children, the auricle is

otoscope, the tube may be straightened by pulling the auri

surface of the tympanic membrane in the adult with an

long and forms an S-shaped curve. To examine the outer

11.27). The external auditory meatus is about 1 in. (2.5 cm)

These structures lie in front of the mastoid process (Fig.

end of the second year.

her head. It can be recognized as a bony projection at the

pull of the sternocleidomastoid, as the child moves his or

in the newborn child and grows only as the result of the

behind the ear (Figs. 11.128 and 11.131). It is undeveloped

The mastoid process projects downward and forward from

Mastoid Process of the Temporal Bone

pezius and sternocleidomastoid muscles.

process of the temporal bone. It gives attachment to the tra

ally from the external occipital protuberance to the mastoid

The superior nuchal line is a curved ridge that runs later

frontal air sinuses.

11.128). Deep to these ridges on either side of the midline

frontal bones above the upper margin of the orbit (Fig.

The superciliary ridges are two prominent ridges on the

by the end of the first year.

of the two parietal bones (Fig. 11.128). It is usually closed

mous part of the occipital bone and the posterior borders

In the baby, the posterior fontanelle lies between the squa

18 months.

bones behind (Fig. 11.128). It is usually not palpable after

halves of the frontal bone in front and the two parietal

In the baby, the anterior fontanelle lies between the two

plane (Fig. 11.128).

The vertex is the highest point on the skull in the sagittal

Vertex

663

Anterior Fontanelle

Posterior Fontanelle

Superciliary Ridges

lie the

Superior Nuchal Line

Auricle and External Auditory Meatus

The tympanic membrane is normally pearly gray and is

on deep palpation when this muscle is relaxed.

mandible is covered by the masseter muscle and can be felt

through the skin. The outer surface of the ramus of the

by the parotid gland (Fig. 11.85), but below it is easily felt

The posterior border of the ramus is overlapped above

band on its medial side.

the pterygomandibular ligament can be palpated as a tense

can be felt with the gloved finger inside the mouth, and

masseter muscle. The coronoid process of the mandible

The anterior border of the ramus can be felt deep to the

ward below the tubercle of the zygomatic arch.

is opened, the head of the mandible rotates and moves for

front of the auricle (Fig. 11.128). Note that as the mouth

The temporomandibular joint can be easily palpated in

Temporomandibular Joint

mastoid antrum.

of the

meatus. The bony floor of the triangle forms the lateral wall

of the temporal bone, and below by the external auditory

external auditory meatus, above by the suprameatal crest

drawn vertically upward from the posterior margin of the

(Fig. 11.128). This is bounded behind by a line

triangle

suprameatal

the auricle, can be felt a small depression, the

Above and behind the external auditory meatus, deep to

geal artery.

anterior branch of the middle menin

beneath it lies the

eminence or a depression, but it is important because

zygomatic arch (Fig. 11.128), it is not marked by an

bone. Lying 1.5 in. (4 cm) above the midpoint of the

sphenoid meets the anteroinferior angle of the parietal

The pterion is the point where the greater wing of the

auricle (Fig. 11.128).

as it crosses the zygomatic arch, immediately in front of the

The pulsations of the superficial temporal artery can be felt

Superficial Temporal Artery

can be felt by clenching the teeth.

of both the temporalis and masseter muscles (Fig. 11.85)

Contraction

masseter muscle.

of the zygomatic arch is the

Attached to the lower margin

temporalis muscle.

with the

which is filled

temporal fossa,

the zygomatic arch is the

ends in front in the zygomatic bone (Fig. 11.128). Above

The zygomatic arch extends forward in front of the ear and

surface.

the attachment of the handle of the malleus on its medial

and is caused by

umbo

part of the concavity is called the

concave toward the meatus (Fig. 11.27). The most depressed

Zygomatic Arch

Pterion

Anterior Border of the Ramus of the

Mandible

Posterior Border of the Ramus of the

Mandible

Surface Anatomy

675

medial rectus
muscle

lateral
rectus

muscle

temporal

lobe

optic
chiasma

optic
nerve

eyeball

ethmoid
sinuses

FIGURE 11.127

al and the cranial cavities. Note that the eyeballs, the

Axial (horizontal) MRI showing the contents of the orbit

optic nerves, the optic chiasma, and the extraocular muscles can be identified.

vertex

central sulcus

parietal eminence

posterior branch

of the middle meningeal artery

superficial temporal artery

suprameatal crest

external occipital protuberance

suprameatal triangle

mastoid process

zygomatic arch

ramus of mandible

angle of mandible

body of mandible

symphysis menti

coronoid process

articular tubercle

temporomandibular joint

nasion

superciliary ridge

pterion

anterior branch of the middle meningeal artery

motor area of cerebral cortex

posterior fontanelle

anterior fontanelle

posterior fontanelle

anterior fontanelle

FIGURE 11.128

Superior aspect and right side of the neonatal skull. Note the positions of the anterior and posterior fontanelles.

Right side of the head showing relations of the middle meningeal artery and the brain to the surface of the

skull. B.

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CHAPTER 11

the second, third, and fourth rings of the trachea

This lies in front of

Isthmus of the thyroid gland:

pation just above the isthmus of the thyroid gland.

This can be felt by gentle pal

First ring of the trachea:

trachea (Fig. 11.98).

val between the cricoid cartilage and the first ring of the

This structure fills in the inter

Cricotracheal ligament:

enters the thyroid gland.

glion, and at the level where the inferior thyroid artery

gus, at the level of the middle cervical sympathetic gan

the level of the junction of the pharynx with the esopha

vertebra, at the junction of the larynx with the trachea, at

(Fig. 11.129), this lies at the level of the 6th cervical

An important landmark in the neck

Cricoid cartilage:

lage (Fig. 11.130).

val between the cricoid cartilage and the thyroid carti

This structure fills in the inter

Cricothyroid ligament:

structure lies opposite the 4th cervical vertebra (Figs.

This notched

Upper border of the thyroid cartilage:

(Fig. 11.130).

between the hyoid bone and the thyroid cartilage

This fills in the interval

Thyrohyoid membrane:

cal vertebra (Figs. 11.13 and 11.129).

This lies opposite the 3rd cervi

Body of the hyoid bone:

are located in this triangle.

by the mylohyoid muscle. The submental lymph nodes

orly by the body of the hyoid bone. The floor is formed

by the anterior belly of the digastric muscle, and inferi

bounded anteriorly by the midline of the neck, laterally

menti and the body of the hyoid bone (Fig. 11.56). It is

This lies between the symphysis

Submental triangle:

midline (Figs. 11.129 and 11.130).

the two halves of the body of the mandible unite in the

The lower margin can be felt where

Symphysis menti:

palpated from above downward:

In the midline anteriorly, the following structures can be

lies deep to the superciliary ridge on each side (Fig. 11.97).

The frontal air sinus is situated within the frontal bone and

(Fig. 11.97).

bone and lies below the infraorbital foramen on each side

The maxillary air sinus is situated within the maxillary

plies the skin of the face.

The infraorbital nerve emerges from the foramen and sup

premolar teeth.

supraorbital notch to the interval between the two lower

of the orbit (Fig. 11.1), on a line drawn downward from the

The infraorbital foramen lies 5 mm below the lower margin

against the bone (Fig. 11.18).

which can be rolled

supraorbital nerve,

It transmits the

and intermediate thirds of the upper margin of the orbit.

If present, the notch can be felt at the junction of the medial

maxillary bones (Fig. 11.18).

The orbital margin is formed by the frontal, zygomatic, and

mouth opposite the upper second molar tooth (Fig. 11.72).

der of the masseter as it turns medially and opens into the

be rolled beneath the examining finger at the anterior bor

fingerbreadth below the zygomatic arch (Fig. 11.132). It can

The parotid duct runs forward from the parotid gland one

clenching the teeth.

The anterior border of the masseter can be easily felt by

rior border of the masseter muscle (Fig. 11.132).

the lower margin of the body of the mandible, at the ante

The pulsations of the facial artery can be felt as it crosses

angle of the mandible (Fig. 11.128).

sis menti, in the midline anteriorly, as far backward as the

it is possible to examine the mandible from the symphy

finger inside the mouth and another on the outside. Thus,

The body of the mandible is best examined by having one

The Head and Neck

Body of the Mandible

Facial Artery

Anterior Border of the Masseter

Parotid Duct

Orbital Margin

Supraorbital Notch

Infraorbital Foramen

Infraorbital Nerve

Maxillary Air Sinus

Frontal Air Sinus

Surface Landmarks of the Neck

Anterior Aspect

■

11.13 and 11.129).

■

-
-

■

-
-

■

(Figs. 11.129 and 11.130).

lar veins just above the suprasternal notch (Fig. 11.13).

This vein connects the two anterior jugu

Jugular arch:

gland, from the brachiocephalic artery (Fig. 11.110).

in front of the trachea to the isthmus of the thyroid

When present, this artery ascends

Thyroidea ima artery:

(Fig. 11.110).

front of the fifth, sixth, and seventh rings of the trachea

The inferior thyroid veins lie in

Inferior thyroid veins:

■

Surface Anatomy

677

angle of mandible

triangle of neck

posterior

triangle of neck

trapezius

sternocleidomastoid

suprasternal notch

symphysis menti

body of hyoid

thyroid cartilage

cricoid cartilage

isthmus of
thyroid gland

trachea

FIGURE 11.129

-old woman. Note that the atlanto-occipital joints and the cervi

Anterior view of the head and neck of a 29-year

In the adult, the trachea may measure as much as 1 in.

vertebra.

the lower border of the body of the 2nd thoracic

rior border of the manubrium sterni and lies opposite

rior ends of the clavicles (Fig. 11.129). It is the supe

This can be felt between the ante

Suprasternal notch:

cal part of the vertebral column are partially extended for full exposure of the front of the neck.

■

-
-

(2.5 cm) in diameter, whereas in a baby it may be nar

cleidomastoid, and the midline (Fig. 11.56). The posterior

neck is bounded by the body of the mandible, the sterno

rior and posterior triangles. The anterior triangle of the

The sternocleidomastoid divides the neck into ante

tract, and its anterior and posterior borders will be defined.

carried out against resistance, the muscle will be felt to con

looks upward toward the opposite side. If the movement is

side and at the same time rotate the head so that the face

patient to approximate the ear to the shoulder of the same

11.132). The muscle can be made to stand out by asking the

sternum and clavicle to the mastoid process (Figs. 11.131 and

pated throughout its length as it passes upward from the

On the side of the neck, the sternocleidomastoid can be pal

Sternocleidomastoid Muscle

ligamentum nuchae.

Cervical spines one to six are covered by

bra prominens).

7th cervical vertebra (verte

process to be felt is that of the

The first spinous

nuchal groove.

drawn downward in the

index finger is placed on the skin in the midline, it can be

at the junction of the head and neck (Fig. 11.132). If the

lies in the midline

external occipital protuberance

The

palpated from above downward.

In the midline posteriorly, the following structures can be

suprasternal notch.

and the left brachiocephalic vein may protrude above the

mus of the thyroid gland, and the brachiocephalic artery

may extend above the suprasternal notch as far as the isth

rower than a pencil. In young children, the thymus gland

Posterior Aspect

the

Lateral Aspect

triangle is bounded by the anterior border of the trapezius,

border of the lateral third of the clavicle.

occipital bone, downward and forward to the posterior

will be seen to extend from the superior nuchal line of the

can be felt by asking the patient to shrug the shoulders. It

The anterior border of the trapezius muscle (Fig. 11.129)

Trapezius Muscle

the sternocleidomastoid, and the clavicle (Fig. 11.56).

678

CHAPTER 11

The Head and Neck

symphysis menti

body of hyoid bone

angle of mandible

superior belly of

the omohyoid muscle

sternohyoid muscle

thyroid cartilage

thyroid gland

sternothyroid muscle

isthmus of thyroid gland

suprasternal notch

trachea

trapezius muscle

inferior belly of the

omohyoid muscle

cricothyroid ligament

sternocleidomastoid muscle

thyrohyoid membrane

posterior belly of the

digastric muscle

submandibular salivary gland

mylohyoid muscle

anterior belly of

the digastric muscle

FIGURE 11.130

Surface anatomy of the neck from in front.

seated patient and asking the patient to flex the neck for

This is most easily carried out by standing behind the

be palpated deep to the sternocleidomastoid muscles.

and 11.130). The lateral lobes of the thyroid gland can

ond, third, and fourth rings of the trachea (Figs. 11.129

The isthmus of the thyroid gland lies in front of the sec

Anterior Triangle of the Neck

be identified.

sternoclavicular joint

medial end of the clavicle, the

lateral extremity with the acromion of the scapula. At the

can be easily palpated (Fig. 11.132). It articulates at its

clavicle is subcutaneous throughout its entire length and

midline anteriorly (see page 677) and the clavicles. Each

suprasternal notch

At the root of the neck are the

Root of the Neck

the anterior thoracic wall (Fig. 11.51).

the body of the mandible downward over the clavicle onto

patient to clench the jaws firmly. The muscle extends from

The platysma can be seen as a sheet of muscle by asking the

Platysma Muscle

in the

can

Surface Anatomy

679

suprasternal notch

sternocleidomastoid

sternal head of

triangle of neck

body of mandible

(third part)

site of subclavian artery

brachial plexus

triangle of neck

posterior

ternal

mastoid process

trapezius

jugular vein

site of

angle of mandible

FIGURE 11.131

ear-old man. Note that the head has been laterally rotated to the left at the

Anterior view of the neck of a 27-y

duct is given on page 631.

muscle (Fig. 11.85). The surface marking of the parotid

dible and the anterior border of the sternocleidomastoid

gland lies below the ear in the interval between the man

The three large salivary glands can be palpated. The parotid

Salivary Glands

vian vein.

fascia just above the clavicle and drains into the subcla

clavicle (Figs. 11.131 and 11.132). It perforates the deep

region of the angle of the mandible to the middle of the

cia deep to the platysma. It passes downward from the

The external jugular vein lies in the superficial fas

External Jugular Vein

enter the neck.

The subclavian vein lies behind the clavicle and does not

surface of the 1st rib, that its pulsations can be felt easily.

of the clavicle. It is here, where the artery lies on the upper

about 0.5 in. (1.3 cm) and then downward to the middle

which passes upward from the sternoclavicular joint for

and 11.132). Its course may be indicated by a curved line,

lower anterior angle of the posterior triangle (Figs. 11.131

The third part of the subclavian artery also occupies the

Third Part of the Subclavian Artery

middle of the clavicle.

by a line drawn from the cricoid cartilage downward to the

and 11.132). The upper limit of the plexus can be indicated

lower anterior angle of the posterior triangle (Figs. 11.131

The roots and trunks of the brachial plexus occupy the

Roots and Trunks of the Brachial Plexus

angle; the second line indicates the course of the nerve.

and extend the second line downward across the posterior tri

to the tip of the mastoid process. Bisect this line at right angles

cated as follows: Draw a line from the angle of the mandible

trapezius (Fig. 11.132). The course of this nerve may be indi

ward and backward to pass beneath the anterior border of the

posterior border of the sternocleidomastoid and runs down

is relatively superficial as it emerges from the

accessory nerve

At the posterior triangle of the neck, the spinal part of the

Posterior Triangle of the Neck

ies can be felt at this level.

carotid arteries (Fig. 11.132). The pulsations of these arter

mon carotid artery bifurcates into the internal and external

level of the upper border of the thyroid cartilage, the com

the mastoid process and the angle of the mandible. At the

sternoclavicular joint to a point midway between the tip of

cal lymph nodes, can be marked out by a line joining the

internal jugular vein, the vagus nerve, and the deep cervi

The carotid sheath, which contains the carotid arteries, the

Carotid Sheath

the fingers of both hands.

then examine both lobes simultaneously with the tips of

ward and so relax the overlying muscles. The observer can

atlantoaxial joints and at the joints of the cervical part of the vertebral column.

680

CHAPTER 11

The Head and Neck

mastoid process

angle of

mandible

external occipital

protuberance

spinal part

of the accessory nerve

external jugular vein

trapezius

inferior belly of omohyoid

acromion

brachial plexus

clavicle

subclavian artery

sternocleidomastoid

isthmus of thyroid gland

trachea

cricoid cartilage

thyroid cartilage

common carotid artery

hyoid bone

digastric muscle

external

carotid artery

facial artery

masseter muscle

internal jugular vein

parotid duct

zygomatic arch

head of mandible

FIGURE 11.132

Surface anatomy of the neck from the lateral aspect.

Surface Anatomy

beneath the lower margin of the body of the mandi

superficial and deep parts. The superficial part lies

The submandibular gland can be divided into

681

ble (Fig.

eep part of the submandibular

11.86). The d

tongue (Fig. 11.72).

opens into the mouth on the side of the frenulum of the

the tongue and the lower jaw. The submandibular duct

covering the floor of the mouth in the interval between

gland can be palpated through the mucous membrane

gland, the submandibular duct, and the sublingual

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Surface anatomy of the head and neck

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