7 Chapter8 Upper Limb

7/27/2019 7 Chapter8 Upper Limb

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Chapter 8

The Upper Limb

Introduction

For descriptive purpose, the upper limb in each side is usually divided into five parts: the

shoulder, the arm, the elbow, the forearm and the hand.

The shoulder region includes the axilla, the scapular region and the deltoid region. The arm

and the forearm can be divided into anterior and posterior regions. The hand can be divided into the

palm, the dorsum and the fingers.

IntroductionIntroduction

The HandThe Hand

The ShoulderThe Shoulder

The ArmThe Arm

The ElbowThe Elbow

The ForearmThe Forearm

DivisionsDivisions

The pectoral region & axillary region

1. Boundaries of the axillary cavity

The axillary is a pyramidal region. So it has an apex, a base and four walls.

The apex The apex of the cavity is directed upwards to the root of the neck, and is formed by the

first rib, the superior border of the scapula, the posterior surface of clavicle.

The base The base of the cavity is is directed downwards, formed by the skin, the superficial

fascia and the axillary fascia.


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latissimus dorsi, the scapula.

In the posterior wall, there two important structures: the trangular space and the quadrangular space.

The trangular space is the triangular space between the teres minor, the teres major, and the long

head of the triceps brachii. It is pierced by the circumflex scapular vessels. The quadrangular space

is the quadrangular space between the teres minor, the teres major, the long head of the brachii and

the surgical neck of the humerus. It is pierced by the axillary nerve and the posterior humeral

circumflex vessels.

Quadrangular spaceQuadrangular space (( ))

Triangular spaceTriangular space (( ))

TeresTeres minor/minor/ SubscapularisSubscapularis(( // ))TeresTeres majormajor (( ))Surgical neck of theSurgical neck of the humerushumerus (( ))Long head of tricepsLong head of triceps brachiibrachii (( ))

the circumthe circum--flex scapular vesselsflex scapular vessels(( ))..

the posterior humeral circumflexthe posterior humeral circumflex

vesselsvessels (( ))..

thethe axillaryaxillary nervenerve

The medial wall The medial wall is formed by first four ribs and their intercostal muscles, and

the upper part of the serratus anterior.


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The lateral wall The lateral wall is formed by the long head and the short head of the biceps

brachii, the coracobrachialis, and the intertubercular sulcus of the humerus.

5. The medial wall5. The medial wall

Formed by:Formed by:

6. The lateral wall6. The lateral wall

Formed by:Formed by:

1st1st------4th ribs and the4th ribs and the intercostalintercostal musclesmuscles

the two heads of thethe two heads of the

bicepsbiceps brachiibrachii(( ))

thethe intertubercularintertubercular sulcussulcus of theof the

humerushumerus (( ))

the upper part of thethe upper part of the serratusserratus anterioranterior (( ))

thethe coracobrachialiscoracobrachialis(( ))

2. Contents of the axillary cavity

The main contents in the cavity include the axillary artery and its branches, the axillary vein and its

tributaries, the brachial plexus and its branches, the axillary lymph nodes. And at same time there

are many fat and loose connective tissue in it.

The axillary artery The axillary artery were divided into three parts by the pectoralis minor.

In the first part, there is only one branch, the superior thoracic artery., it supplies the anterior part of

the first and the second intercostal spaces.There are two branches coming from the trunk, the throracoacromial artery and the lateral thoracic

artery. The throracoacromial artery pierces the clavipectoral fascia and divides into three branches

immediately, one to the deltoid, one to the acromion, and the other goes to the pectorals. The lateral

thoracic artery goes along the lower border of the pectoralis minor, mainly supplies the structures of

the thoracic wall. In women, this artery is lager and gives the branch to breast.

There are three branches in the third part. The first is the subscapular artery. Usually this artery is

the largest branch of the trunk. It has two branches: the circumflex scapular artery and the

thoracodorsal artery. The circumflex artery pierces the triangular space to the back of the shoulder.

The thoracodorsal artery goes to the latissimus dorsi. In the third part there are two arteries go

around humerus, the anterior humeral circumflex artery and the posterior humeral circumflex artery.

The posterior humeral circumflex artery pierces the quadrangular space with the axillary nerve.


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The main branches of the brachial plexus There are many branches coming from the three

cords of the brachial plexus, but the most important branches are the musculocutaneous nerve, the

median nerve, the ulnar nerve, the radial nerve and the axillary nerve.


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2. The main branches of the brachial plexus2. The main branches of the brachial plexus

thethe musculocutaneousmusculocutaneous nervenerve

(( )) the median nervemedian nerve ( ) thethe ulnarulnar nervenerve (( )) the radial nervethe radial nerve (( ))

thethe humeromuscularhumeromuscular tunneltunnel(( )) thethe axillaryaxillary nervenerve (( ))

the quadrangular spacethe quadrangular space

the long thoracic nervethe long thoracic nerve ((

thethe thoracodorsalthoracodorsal nervenerve ((

The axillary sheath The prevertebral layer of the deep cervical fascia extends from the neck and

through the apex to the axillary cavity, in the cavity it enclose the axillary artery, the axillary vein

and the brachial plexus, we call it axillary sheath.

Because the fascia of the sheath comes from the prevertebral layer, so if there is a prevertebral


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abscess, the pus maybe spread to axilla through the axillary sheath. And when the surgical operation

doing only on the lower part of the limb, we can inject the anesthetic into the axillary sheath to

block the bracial plexus. But be careful not damage the artery. So the operator should first touch the

axillary according to its pulsation. And then insert the needle superior or inferior to the palpating

index finger.

The axillary lymph nodes There are many lymph nodes in the axillary cavity and were divided into five

groups. The nodes arrange along lower border of the pectoralis minor called the pectoral lymph nodes. The

pectoral lymph nodes receive the vessels from the anterior and lateral thoracic wall, the central and lateral parts of

the breast. The nodes arrange near the distal part of the axillary vein called the lateral lymph nodes and they

receive the vessels from the upper limb. The nodes arrange near subscapular vessels called the subscapular lymph

nodes and they receive the vessels from the scapular region and the back. The efferent vessels of these three group

drain into the center group. The center group lies in the fat of the axillary cavity. And its efferent vessels drain

into the apical nodes. The apical nodes arrange near the upper part of the axillary cavity and receive the vessels

from the center group and the upper part of the breast. And their efferent vessels form the subclavian trunk.

The lymphatic drainage of the breast The cancer of breast is a common tumour happening in

wemen, and it can spread through the lymphatic vessels. So studying the lymphatic drainage of the

breast is very important.

Usually there are four pathways for lymphatic drainage:

The lymphatic vessels of the lateral and upper parts drain into the pectoral lymph nodes, this isthe main lymphatic drainage of the breast, and usually is invaded early by the beast cancer.

The lymphatic vessels of the medial parts drain into the parasternal lymph nodes. These vesselscan anastomose with the contralateral lymphatic vessels.


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The lymphatic vessels of the inferomedial parts anastomose with the lymphatic vessels of theanterior abdominal wall , the subdiaphragmatic and hepatic lymphatic vessels.

The deep lymphatic vessels of the breast pierce the pectoralis major and minor directly anddrain into the apical lymph nodes.

Axillary nodes receive more than 75% of lymph from the gland, and the remainder largely draining

to parasternal nodes. So in the radical mastectomy, the pectoralis major and minor, the accessible

lymph nodes must be removed thoroughly. When the operator working, he must be careful not to

damage those important vessels and nerves going nearby. For example, when cutting the pectoralis

major and minor, dealing with the clavipectoral dascia or removing the apical lymph nodes, he

should protect the cephalic vein from damage. And when removing the pectoral lymph nodes, he

should protect the long thoracic nerve; and when removing lateral and central lymph node, heshould protect vessels and nerves in the axillary cavity especially the axillary vein; And when

removing the subscapular lymph nodes you should protect the thoracodorsal nerve.The anterior region of the arm, the elbow, the forearm, and the wrist.

The superficial vein There are two larger veins here. One is the cephalic vein, and the other is the

basilic vein. The cephalic vein begins at the radial side of the dorsal venous rete of hand, and

ascends to the elbow at the lateral side of the forearm, then goes into the cleft between the pectoralis

major and deltoid, pierces the clavipectoral fascia and drains into the axillary vein.


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Main ContentsMain Contents

1. Superficial veins

1) The cephalic vein (( ))begins at the radial side of the dorsal

venous rete of hand( )ascends in the anterolateral part of

the forearm to the elbow runs

along the lateral bicipital groove

runs along the interval between the

deltoid and pectoralis majorpierces the clavipectoral fascia

ends in the axillary vein.

1)

1)

2)

2)

And the basilic vein begins at the unlar side of the dorsal venous rete of hand and ascends to the

elbow at the medial side of the forearm, and then goes along the medial bicipital groove and pierces

the deep fascia of the arm and drain into the axillary vein.Some times there is a superficial vein connecting the cephalic vein and the basilic vein at the elbow.

We call it the median cubital vein. Usually it comes from the cephalic vein and drain into the basilic

vein upward and medially. Vein punctures are often performed at upper limb with these superficial

veins. Usually there is a large superficial vein at the anterior aspect of the elbow, sometimes maybe

it is the median cubital vein, and this superficial vein is connected with the deep vein, so we often

make the vein punctures at the elbow.


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3) The median cubital vein (( ))Often divided from the cephalic vein at the

cubital fossa. Connects the cephalic vein with

the basilic vein, slants upwards and medially

superficially

Vein punctures are often performed at theVein punctures are often performed at the

elbow, and the largest vein usually the medianelbow, and the largest vein usually the median

cubitalcubital vein, is selected.vein, is selected.

begins from the ulnar side of the dorsal venous

rete of hand ascends on the posterior

surface of the ulnar side of the forearm

inclines forwards to the anterior surface below

the elbow runs upwards along the medialbicipital groove perforates the deep fascia

a little below the middle of the arm ends in

the axillary vein at the lower border of teres

major.

2) The basilic vein(( ))

2)

2)

3)

The cubital fossa. The cubital fossa is a triangular depression. If you remove the skin and the

superficial fascia you will find that all the content are deep to the aponeurosis of the biceps brachii

and the deep fascia, so we can say the roof of the fossa is formed by the aponuerosis and the deep

fascia. Then if you remove the deep fascia and cut off the apoeurosis, you can find the upper

boundary is formed by an imaginary line connecting the two humeral epicondyles. The pronator

teres is the inferomedial boundary and the brachioradialis is the inferolateral boundary. And the

brachialis and supinator form the base of the fossa, and deep to all the content.


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The contents in the cubital fossa arrange in a regular order. From the lateral side to the medial side, is the tendon

of the biceps brachii, the terminal part of the brachil artery, and then the median nerve. At the lower part of the

fossa the brachil artery divides into two branches: the radial artery and the ulnar artery.

The carpal canal First lets learn something about the deep fascia of the wrist. The deep fasciahere includes two layers. The superficial layer of the deep fascia we call it the palmar carpal

ligament. It is thickened by some transverse fibers. And the deep layer extends distally, we call it

the flexor retinaculum. It is very thick. Both the ulnar end and the radial end of it is attached to

some carpal bones. So there is a canal between the flexor retinaculum and the groove of the carpal

bones, we call it the carpal canal.

3.3. The carpal canalThe carpal canal The superficial layer ---- the palmar carpal ligament( )The deep layer ---- extends distally as the flexor retinaculum( )

(1)

(2) The flexor(2) The flexor retinaculumretinaculum( transverse carpal ligament)( transverse carpal ligament)

thethe ulnarulnar end is attached to theend is attached to the pisiformpisiform( ) and the hook ofand the hook ofhamatehamate( ), and the radial end is attached to the tubercles of, and the radial end is attached to the tubercles ofscaphoidscaphoid( ) andandtrapeziumtrapezium( ).).

palmar carpal

ligament

flexorflexorretinaculumretinaculum

carpalcanal

The deep fascia of the anterior carpal regionThe deep fascia of the anterior carpal region

The median nerve and nine tendons pass through the carpal canal to the palm. The nine tendons

include the flexor digitorum superficialis, the tendons of the flexor digitorum profundus and the

tendon of the pollicis longous. Because the flexor retinaculum is very thick, so it can protect the

tendons and the median nerve from some damage. But at the same time, any disease in the canal

may injure the median nerve. And the deep space of the forearm can communicates with the space

of palm through the carpal canal. So the infection of the palm may extend to the forearm through

this way.


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(3) The carpal canal) The carpal canal Formed by :

the flexor retinaculum

the groove of the carpal bones.

Contents:

the tendons of the flexor digitorum superficialis( )the tendons of the flexor digitorum profundus( )the tendons of the flexor pollicis longous ( )the median nerve.

palmar carpalligament

flexorflexorretinaculumretinaculum

carpalcanal

The posterior region of the arm, the elbow, the forearm , and the wrist.

The humeromuscular tunnel. It is located at the middle part on the back of the arm. And it

extends downwards from the superomedial side to the inferolateral side. It is formed by the three


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heads of the triceps brachii and the sulcus for the radial nerve on the humerus. The radial nerve and

deep brachial vessels pass through the humeromuscular tunnel. So if there is a fracture at the

humeral shaft, the radial nerve may be injured. over the cadaver to the prone position, abduct the

upper limb and then make the incisions. Here we have two transverse incisions, one at the arm and

the other at the wrist. Both of them continue with the anterior incisions. At the dorsum of hand, you

should make a longitudinal incision in the midline and a curve incision along all themetacarpophalangeal joints.

7 Chapter8 Upper Limb

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