Surface anatomy of the upper limb pdf - Upper limb

418

CHAPTER 9

The Upper Limb

glenoid

ateral

dial

rib

fir

acoid proces

ity

uberos

greater

hum erus

head of

acrom ion

cor

clavicle

m e

borde of scapu

border of scapula

ssa

anatom

surgica neck

ic neck

FIGURE 9.86

Anteroposterior radiograph of the shoulder region in the adult.

natomy

aphic

adiog

Radiographic Appearances of the

(Fig. 9.94).

useful to demonstrate the soft tissues around the bones

Magnetic resonance imaging of the upper limb can be

Figures 9.86 through 9.93.

radiographic appearances of the upper limb are shown in

dons, and nerves blend into a homogeneous mass. The

mainly on the bony structures because the muscles, ten

Radiologic examination of the upper limb concentrates

Upper Limb

natomy

face

Anterior Surface of the Chest

projects above the margin of the manubrium sterni.

easily identified. Note that the medial end of the clavicle

of the sternoclavicular and acromioclavicular joints can be

easily palpated (Figs. 9.95, 9.96, and 9.97). The positions

out its entire length lies just beneath the skin and can be

The clavicle is situated at the root of the neck and through

9.96, and 9.97).

ribs and the ends of the 11th and 12th cartilages (Figs. 9.95,

is formed by the cartilages of the 7th, 8th, 9th, and 10th

The costal margin is the lower boundary of the thorax and

sternum and the body of the sternum (Fig. 9.97).

The xiphisternal joint is between the xiphoid process of the

costal cartilage joins the lateral margin of the sternum.

the body of the sternum (Fig. 9.95); at this level, the 2nd

The sternal angle is the angle between the manubrium and

medial ends of the clavicles in the midline (Figs. 9.95 and 9.96).

brium sterni and is easily palpated between the prominent

The suprasternal notch is the superior margin of the manu

Suprasternal Notch

Sternal Angle (Angle of Louis)

Xiphisternal Joint

Costal Margin

Clavicle

Surface Anatomy

is formed by the lower margin

anterior axillary fold

The

and deltoid muscles (Figs. 9.95 and 9.96).

third of the clavicle and is bounded by the pectoralis major

This small, triangular depression is situated below the outer

Deltopectoral Triangle

column) and counting down from there.

sternal angle and the 2nd costal cartilage (see previous

(Fig. 9.97). Each rib can be identified by first palpating the

them downward over the lateral surface of the chest wall

pressing the fingers upward into the axilla and drawing

The lateral surfaces of the remaining ribs can be felt by

The 1st rib lies deep to the clavicle and cannot be palpated.

419

Ribs

Axillary Folds

of the pectoralis major muscle and can be palpated between

and the pectoral muscles relaxed. With the arm by the side,

The axilla should be examined with the forearm supported

be easily palpated between the finger and thumb (Fig. 9.98).

around the lower border of the teres major muscle. It can

is formed by the tendon of latissimus dorsi as it passes

fold

posterior axillary

her hand against the ipsilateral hip. The

be made to stand out by asking the patient to press his or

the finger and thumb (Figs. 9.95, 9.96, and 9.97). This can

Axilla

humerus

lateral epicondyle

capitulum

radial fossa

neck

head

bicipital tuberosity

ulna

radius

coronoid process

trochlea

medial epicondyle

olecranon fossa

FIGURE 9.87

Anteroposterior radiograph of the elbow region in the adult.

Surface Anatomy

423

flexor

pollicis

longus

flexor
digitorum
profundus

ulna

brachioradialis

radius

basilic
vein

extensor
carpi
ulnaris

cephalic

vein

interosseous

membrane

radial artery and

superficial branch

of radial nerve

anterior median vein

of forearm

flexor

carpi

radialis

flexor

digitorum

superficialis

extensor
pollicis
longus

median nerve

FIGURE 9.94

Transverse (axial) magnetic resonance image of the upper part of the right forearm (as seen from below).

clavicle

acromion process

greater tuberosity

of humerus

deltoid

areola

nipple

costal margin

rectus abdominis

umbilicus

iliac crest

xiphoid process

axillary tail
of mammary gland

anterior
axillary fold

pectoralis major

sternal angle
(angle of Louis)

deltopectoral triangle

suprasternal
notch

FIGURE 9.95

Anterior view of the thorax and abdomen in a 29-year-old woman.

424

CHAPTER 9

The Upper Limb

deltoid

greater
tuberosity
of humerus

acromion

deltopectoral
triangle

trapezius

suprasternal

notch

sternocleidomastoid

supraclavicular
fossa

clavicle

clavicular head
of pectoralis major

sternocostal head
of pectoralis major

biceps
brachii

triceps

anterior
axillary fold

costal margin

rectus
abdominis

origin

of serratus

median
cubital
vein

cubital fossa

lateral
epicondyle
of humerus

xiphoid

process

medial
epicondyle
of humerus

FIGURE 9.96

The pectoral region in a 27-year-old man.

sternal angle

pectoralis major

deltoid

anterior axillary fold

biceps

cephalic vein

serratus anterior

lateral epicondyle

brachioradialis

biceps tendon

bicipital aponeurosis

basilic vein

cubital fossa

medial epicondyle

coracobrachialis

xiphoid process

costal margin

nipple

greater
tuberosity

head of humerus

acromion

coracoid process

clavicle

suprasternal notch

FIGURE 9.97

Surface anatomy of the chest, shoulder, and upper limb as seen anteriorly.

Surface Anatomy

located (Figs. 9.95 and 9.96).

of the spine of the scapula. It is subcutaneous and easily

forms the lateral extremity

acromion

deltoid muscle. The

topectoral triangle; it is covered by the anterior fibers of the

can be felt on deep palpation in the lateral part of the del

of the scapula (Fig. 9.97)

coracoid process

The tip of the

ligamentum nuchae.

cervical vertebrae are covered by the large ligament called

of the thoracic vertebrae. The spines of the 1st through 6th

Below this level are the overlapping spines

bra prominens).

(verte

process to be felt is that of the 7th cervical vertebra

drawn downward in the nuchal groove. The first spinous

skin in the midline on the posterior surface of the neck and

riorly (Fig. 9.98). The index finger should be placed on the

The spinous processes can be palpated in the midline poste

Thoracic Vertebrae

the humerus.

and the bicipital groove of

biceps brachii muscles

coracobrachia

(Fig. 9.96). The lateral wall is formed by the

tions of which can be seen and felt in a muscular subject

the serra

serratus anterior muscle,

covered by the

ribs

upper

The medial wall of the axilla is formed by the

cords of the brachial

around the artery can be palpated the

can be felt high up in the axilla, and

axillary artery

of the

ily palpated through the floor of the axilla. The pulsations

can be eas

head of the humerus

the inferior part of the

425

plexus.

lis and

Posterior Surface of the Chest

Spinous Processes of Cervical and

the

Scapula

third
thoracic
spine

seventh
thoracic
spine

posterior
axillary
fold

inferior
angle of
scapula

medial epicondyle

olecranon
process of ulna

lateral
epicondyle

head of humerus

acromion

spine of scapula

superior angle of scapula

greater tuberosity
of humerus

FIGURE 9.98

Surface anatomy of the scapula, shoulder, and

Immediately below the lateral edge of the acromion

elbow regions as seen posteriorly.

is the smooth, rounded curve of the shoulder produced by

traced medially to the medial border of the scapula, which

can be palpated and

crest of the spine of the scapula

The

(Figs. 9.95 and 9.96).

the humerus

greater tuberosity of

which covers the

deltoid muscle,

the

it joins at the level of the 3rd thoracic spine (Fig. 9.98).

becomes darker in color in the second month of the first

(Fig. 9.95). Pink in color in the young girl, the areola

areola

rounded by a circular area of pigmented skin called the

(10 cm) from the midline. The base of the nipple is sur

usually lie over the fourth intercostal spaces about 4 in.

In males and immature females, the nipples are small and

ies greatly and depends on the development of the gland.

(Fig. 9.95), but its position in relation to the chest wall var

projects from the lower half of the breast

nipple

The

ency, produced by its glandular tissue.

open hand, the breast has a firm, overall lobulated consist

contained within it is fluid. On careful palpation with the

In the living subject, the breast is soft because the fat

the breast may be smaller.

breast may be large and pendulous, and in older women

axillary vessels. In middle-aged multiparous women the

(Fig. 9.95), where it comes into close relationship with the

lower border of the pectoralis major and enters the axilla

extends around the

(axillary tail)

Its upper lateral edge

superficial fascia and can be moved freely in all directions.

line (Fig. 9.95). The greater part of the breast lies in the

from the lateral margin of the sternum to the midaxillary

2nd to the 6th ribs and their costal cartilages, and extends

usually hemispherical and slightly pendulous, overlaps the

the pigmented areola. In young women (Fig. 9.95), it is

and the glandular tissue is confined to a small area beneath

In children and men, the breast anatomy is rudimentary

site the 7th thoracic spine (Figs. 9.98 and 9.99).

can be palpated oppo

inferior angle of the scapula

The

the trapezius muscle and lies opposite the 2nd thoracic

can be felt through

superior angle of the scapula

The

spine.

The Breast

acromion

deltoid

infraspinatus

inferior angle
of scapula

spinous
processes
of lumbar
vertebrae

trapezius

teres
major

latissimus
dorsi

iliac
crest

FIGURE 9.99

The back in a 27-year-old man.

426

CHAPTER 9

The Upper Limb

pregnancy and never regains its former tint. Tiny

cles

tuber

The “anatomic snuffbox” is an important area. It is a skin

Anatomic Snuffbox

Lateral Side of the Wrist

Important Structures Lying on the

(Fig. 9.100).

The ulnar nerve lies immediately medial to the ulnar artery

Ulnar Nerve

tendon of flexor carpi ulnaris (Fig. 9.100).

The pulsations of the ulnar artery can be felt lateral to the

Ulnar Artery

fixing and stabilizing the wrist joint).

patient to clench the fist (the muscle contracts to assist in

9.100). The tendon can be made prominent by asking the

distally to its insertion on the pisiform bone (Figs. 9.48 and

placed tendon on the front of the wrist and can be followed

The tendon of the flexor carpi ulnaris is the most medially

Tendon of Flexor Carpi Ulnaris

fingers are flexed and extended.

longus and can be seen moving beneath the skin when the

group of four that lie medial to the tendon of palmaris

The tendons of the flexor digitorum superficialis are a

Tendons of Flexor Digitorum Superficialis

(Fig. 9.100).

don of flexor carpi radialis and overlies the median nerve

The tendon of the palmaris longus lies medial to the ten

Tendon of Palmaris Longus (If Present)

pulsating radial artery.

The tendon of the flexor carpi radialis lies medial to the

Tendon of Flexor Carpi Radialis

of flexor carpi radialis muscle.

it lies just beneath the skin and fascia lateral to the tendon

to the distal third of the radius (Figs. 9.48 and 9.100). Here,

The pulsations of the radial artery can easily be felt anterior

Radial Artery

the Wrist

Important Structures Lying in Front of

flexor retinaculum.

transverse crease corresponds to the proximal border of the

verse crease lies at the level of the wrist joint. The distal

important landmarks (Fig. 9.100). The proximal trans

seen in front of the wrist are

transverse creases

The

a fingerbreadth distal and lateral to the pisiform bone.

can be felt on deep palpation of the hypothenar eminence,

hook of the hamate bone

creases (Figs. 9.48 and 9.100). The

the anterior aspect of the wrist between the two transverse

can be felt on the medial side of

pisiform bone

The

distinguished from the more distal pointed styloid process.

eral side of the wrist (Fig. 9.75). The rounded head can be

pronated; the head then stands out prominently on the lat

is most easily felt with the forearm

head of the ulna

The

terior surface of the distal end of the radius (Fig. 9.100).

is palpable on the pos

dorsal tubercle of the radius

The

lies about 0.75 in. (1.9 cm) distal to that of the ulna.

can be palpated. The styloid process of the radius

(Fig. 9.100)

styloid processes of the radius

At the wrist, the

The Wrist and Hand

and can be palpated along its entire length.

is subcutaneous

posterior border of the ulna bone

The

radius, it divides into the radial and ulnar arteries.

tal aponeurosis, and, at a level just below the head of the

biceps muscle. In the cubital fossa, it lies beneath the bicipi

down the arm, overlapped by the medial border of the

can be felt to pulsate as it passes

brachial artery

The

sation is felt along the medial part of the hand.

cord, and when it is compressed, a “pins and needles” sen

medial epicondyle of the humerus. It feels like a rounded

can be palpated where it lies behind the

ulnar nerve

The

joint is flexed against resistance.

The tendon and aponeurosis are most easily felt if the elbow

cia on the medial side of the forearm (Figs. 9.48 and 9.97).

can be felt as it leaves the tendon to join the deep fas

rosis

bicipital aponeu

passes downward into the fossa, and the

can be palpated as it

tendon of the biceps muscle

ary. The

boundary and the pronator teres forms the medial bound

seen and felt; the brachioradialis muscle forms the lateral

elbow (Figs. 9.48 and 9.97), and the boundaries can be

is a skin depression in front of the

cubital fossa

The

forearm.

be felt to rotate during pronation and supination of the

distal to the lateral epicondyle. The head of the radius can

sion on the posterolateral aspect of the extended elbow,

can be palpated in a depres

head of the radius

The

an equilateral triangle.

elbow is flexed, these three points form the boundaries of

these bony points lie on the same straight line; when the

be palpated (Fig. 9.98). When the elbow joint is extended,

9.96 and 9.98) and the olecranon process of the ulna can

of the humerus (Figs.

lateral epicondyles

medial

The

glands.

areolar

on the areola are produced by the underlying

The Elbow Region

and

-
-

and ulna

box as it ascends the forearm.

can also sometimes be recognized crossing the snuff

vein

cephalic

to reach the dorsum of the hand (Fig. 9.100). The

as the artery winds around the lateral margin of the wrist

can be palpated within the snuffbox

radial artery

ble). The

(felt but not identifia

trapezium

scaphoid

the thumb (distally); between these bones beneath the floor

base of the first metacarpal bone

(proximally) and the

styloid process of the radius

its floor can be palpated the

(Fig. 9.100). In

extensor pollicis brevis

pollicis longus

tendons of abductor

and laterally by the

pollicis longus

tendon of extensor

radius. It is bounded medially by the

depression that lies distal to the styloid process of the

and

lie the

and the

Surface Anatomy

427

superficial

palmar arch

deep palmar arch

hook of hamate

deep branch of ulnar artery

ulnar nerve

distal transverse crease

pisiform bone

proximal transverse crease

flexor carpi ulnaris

ulnar artery

palmaris longus

median nerve

dorsal tubercle of radius

superficial palmar branch

flexor carpi radialis

radial artery

tubercle of scaphoid

ridge of trapezium

of radial artery

base of first metacarpal

trapezium

scaphoid

styloid process of radius

abductor pollicis longus

extensor pollicis brevis

cephalic vein

extensor pollicis

longus

extensor indicis

radial artery

extensor digitorum

extensor digiti minimi

dorsal venous network

extensor retinaculum

flexor retinaculum

FIGURE 9.100

Surface anatomy of the wrist region.

428

CHAPTER 9

pass distally to the bases of the fingers (Fig. 9.100).

can be seen and felt as they

extensor digiti minimi

extensor indicis,

tendons of extensor digitorum,

The

Important Structures Lying on the

finger creases.

lie at the level of the middle and distal

phalangeal joints

inter

level of the distal transverse palmar crease. The

The metacarpophalangeal joints lie approximately at the

Metacarpophalangeal Joints

extended thumb.

the palm at the level of the proximal border of the fully

part of the palm (Fig. 9.100) and lies on a line drawn across

The deep palmar arterial arch is also located in the central

Deep Palmar Arterial Arch

extended thumb.

across the palm at the level of the distal border of the fully

tral part of the palm (Fig. 9.100) and lies on a line drawn

The superficial palmar arterial arch is located in the cen

Superficial Palmar Arterial Arch

of the scaphoid (Fig. 9.62).

ulum and lies about one fingerbreadth distal to the tubercle

nence curves around the lower border of the flexor retinac

The recurrent branch to the muscles of the thenar emi

Recurrent Branch of the Median Nerve

Important Structures Lying in the Palm

when the wrist joint is flexed.

be palpated just distal to the dorsal tubercle of the radius

The lunate lies in the proximal row of carpal bones. It can

Lunate

of the Wrist

Important Structures Lying on the Back

The Upper Limb

-
-

Dorsum of the Hand

the

and the

Arterial Injury

are distributed to the arteries within the branches of the plexus.

the 2nd to 8th thoracic segments of the spinal cord. They ascend

nerves. The preganglionic fibers originate from cell bodies in

ing of the fists closes off the superficial and deep palmar arterial

press the radial arteries against the anterior surface of each

nerve. The artery is commonly damaged here in laceration

artery on the other wrist; occasionally, a congenitally abnormal

carpi radialis; it is here that the clinician takes the radial pulse

artery, as it crosses the first rib to become the axillary artery, can

be palpated or compressed in an emergency. The subclavian

lateral circulation are not diseased and the patient’s general cir

gangrene, provided, of course, that the arteries forming the col

ing wounds or may require ligation in amputation operations.

The arteries of the upper limb can be damaged by penetrat-

Because of the existence of an adequate collateral circulation

around the shoulder, elbow, and wrist joints, ligation of the main

arteries of the upper limb is not followed by tissue necrosis or

culation is satisfactory. Nevertheless, it can take days or weeks

for the collateral vessels to open sufficiently to provide the distal

part of the limb with the same volume of blood as previously sup-

plied by the main artery.

Palpation and Compression of Arteries

A clinician must know where the arteries of the upper limb can

be palpated in the root of the posterior triangle of the neck (Fig.

9.31). The artery can be compressed here against the first rib to

stop a catastrophic hemorrhage. The third part of the axillary

artery can be felt in the axilla as it lies in front of the teres major

muscle (Fig. 9.17). The brachial artery can be palpated in the arm

as it lies on the brachialis and is overlapped from the lateral side

by the biceps brachii (Fig. 9.43).

The radial artery lies superficially in front of the distal end of

the radius, between the tendons of the brachioradialis and flexor

(Fig. 9.58). If the pulse cannot be felt, try feeling for the radial

radial artery can be difficult to feel. The radial artery can be less

easily felt as it crosses the anatomic snuffbox (Fig. 9.100).

The ulnar artery can be palpated as it crosses anterior to the

flexor retinaculum in company with the ulnar nerve. The artery

lies lateral to the pisiform bone, separated from it by the ulnar

wounds in front of the wrist.

Allen Test

The Allen test is used to determine the patency of the ulnar and

radial arteries. With the patient’s hands resting in the lap, com-

radius and ask the patient to tightly clench the fists. The clench-

arches. When the patient is asked to open the hands, the skin of

the palms is at first white, and then normally the blood quickly

flows into the arches through the ulnar arteries, causing the

palms to promptly turn pink. This establishes that the ulnar arter-

ies are patent. The patency of the radial arteries can be estab-

lished by repeating the test but this time compressing the ulnar

arteries as they lie lateral to the pisiform bones.

Arterial Innervation and Raynaud’s Disease

The arteries of the upper limb are innervated by sympathetic

in the sympathetic trunk and synapse in the middle cervical,

inferior cervical, 1st thoracic, or stellate ganglia. The postgan-

glionic fibers join the nerves that form the brachial plexus and

For example, the digital arteries of the fingers are supplied by

postganglionic sympathetic fibers that run in the digital nerves.

Vasospastic diseases involving digital arterioles, such as

Raynaud’s disease, may require a cervicodorsal preganglionic

sympathectomy to prevent necrosis of the fingers. The operation

is followed by arterial vasodilatation, with consequent increased

blood flow to the upper limb.

C L I N I C A L N O T E S O N T H E A R T E R I E S O F T H E U P P E R L I M P

430

CHAPTER 9

The Upper Limb

dermatomes

median nerve

palmar cutaneous

radial nerve

posterior cutaneous branch

palmar
cutaneous
branch

ulnar nerve

C6 C7

FIGURE 9.102

Sensory innervation of the skin of the volar (palmar) and dorsal aspects of the hand; the arrangement of the

dermatomes is also shown.

and will protrude posteriorly, a condition known as

surface of the medial one and a half fingers; the exact cutaneous

branch supplies the extensor carpi radialis brevis and the supi

nerve and continues as the superficial radial nerve. The deep

dyle, it gives off three branches: the nerve to a small part of the

the lateral head of the triceps; and the nerve to the medial head

movement is much impaired. Paralysis of the teres minor is not

der dislocations or fractures of the surgical neck of the humerus.

cord of the brachial plexus (C5 and 6), can be injured by the pres

“winged

scapula” (Fig. 9.8).

Axillary Nerve

The axillary nerve (Fig. 9.24), which arises from the posterior

sure of a badly adjusted crutch pressing upward into the arm-

pit. The passage of the axillary nerve backward from the axilla

through the quadrangular space makes it particularly vulnerable

here to downward displacement of the humeral head in shoul-

Paralysis of the deltoid and teres minor muscles results. The

cutaneous branches of the axillary nerve, including the upper

lateral cutaneous nerve of the arm, are functionless, and con-

sequently there is a loss of skin sensation over the lower half of

the deltoid muscle. The paralyzed deltoid wastes rapidly, and the

underlying greater tuberosity can be readily palpated. Because

the supraspinatus is the only other abductor of the shoulder, this

recognizable clinically.

Radial Nerve

The radial nerve (Fig. 9.25), which arises from the posterior cord

of the brachial plexus, characteristically gives off its branches

some distance proximal to the part to be innervated.
In the axilla, it gives off three branches: the posterior cutaneous

nerve of the arm, which supplies the skin on the back of the arm

down to the elbow; the nerve to the long head of the triceps; and

the nerve to the medial head of the triceps.
In the spiral groove of the humerus, it gives off four branches:

the lower lateral cutaneous nerve of the arm, which supplies the

lateral surface of the arm down to the elbow; the posterior cuta-

neous nerve of the forearm, which supplies the skin down the

middle of the back of the forearm as far as the wrist; the nerve to

of the triceps and the anconeus.
In the anterior compartment of the arm above the lateral epicon-

brachialis, the nerve to the brachioradialis, and the nerve to the

extensor carpi radialis longus.

In the cubital fossa, it gives off the deep branch of the radial

nator in the cubital fossa and all the extensor muscles in the pos-

terior compartment of the forearm. The superficial radial nerve is

sensory and supplies the skin over the lateral part of the dorsum

of the hand and the dorsal surface of the lateral three and a half

fingers proximal to the nail beds (Fig. 9.102). (The ulnar nerve

supplies the medial part of the dorsum of the hand and the dorsal

areas innervated by the radial and ulnar nerves on the hand are

subject to variation.)

The radial nerve is commonly damaged in the axilla and in the

spiral groove.

(continued)

434

CHAPTER 9

basilic veins) links the cephalic and basilic veins in the

(or median cephalic and median

median cubital vein

The

pierces the deep fascia at about the middle of the arm.

the anterior aspect just below the elbow (Fig. 9.39). It

hand around the medial side of the forearm and reaches

can be traced from the dorsum of the

basilic vein

The

in the deltopectoral triangle and enters the axillary vein.

of the biceps (Fig. 9.39). It ends by piercing the deep fascia

then ascends into the arm and runs along the lateral border

winds around onto the anterior aspect of the forearm. It

crosses the anatomic snuffbox and

cephalic vein

The

the lateral cephalic vein and a medial basilic vein.

of the hand (Fig. 9.100). The network drains upward into

The network of superficial veins can be seen on the dorsum

Dorsal Venous Network

The Upper Limb

cubital fossa (Fig. 9.39).

this means, the veins become distended with blood.

the upper arm and repeatedly clench and relax the fist. By

To identify these veins easily, apply firm pressure around

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Review Questions

are available online at

FIGURE 9.105

Ulnar nerve palsy.