7. axilla and brachial plexus

AXILLA

& &

BRACHIAL PLEXUS

•Axillary fossa: a pyramid-shaped space between upper arm and chest.

Boundaries-4 walls, an apex, a base

Anterior wall

Pectoralis major and

minor, clavipectoral

Posterior wall

Subscapularis, clavipectoral fascia

Floor

Axillary fascia, skin,

Subscapularis, teres major

and latissimus dorsi

AXILLA

Pectoralis

Cephalic vein Pectoralis

major

Anterior serratus

Biceps brachii

Coracoid process

minor

major

Axillary vesselsClavipectoral fascia

Teres Teres major

Lat. dorsi

Subscapularis mm

Long thoracic

Teres major

Serratus anterior

Clavicle

Axillary artery

Axillary vein

Brachial plexus

CONTENTS OF AXILLA

Axillary lymphnodes

AXILLA

BRACHIAL PLEXUS

AXILLARY ARTERYAND VEIN

Thoracic Outlet Syndrome

1

Axillary Artery

1

2

3

4

1

1st part – 1 branch

2nd part – 2 branches

Axillary Artery

1

2

3

4

branches

3rd part – 3 branches

Superior thoracic thoracic

artery

P

CA

D

Lateral thoracic

artery

Thoracoacromial artery

PD

Posterior Posterior and

anterior humeral

circumflex arteries Subscapular

artery

Circumflex scapular and thoracodorsal arteries

1

How can blood get to the arm and forearm when there is blockage or ligation of the axillary artery?

Subclavian a.

Thyrocervical a.Transverse cervical a.Suprascapular a.

Posterior and anterior humeral circumflex 1

2

3

4

circumflex aa.

Subscapular a.

Circumflex scapular a.

Branch oftransversecervical a.

Suprascapular a.

Scapular anastomosis

Circumflex scapular a.

Posterior humeralcircumflex a.

1

How can blood get to the arm and forearm when there is blockage or ligation of the axillary artery?

1

2

3

4

Circumflex scapular a.

Anterior view

subscapularis

Quadrangular space

Axillary nerve and posterior humeral circumflex

Triangular space

artery circumflex scapular artery

Posterior view Suprascapular artery and nerve

?

?

Triangular interval (radial n. and deep brachial a.)

BRACHIAL PLEXUS

Axillary sheath

C5

C6

C7

C8

5 roots

3 trunks

6 divisions

3 cords

BRACHIAL PLEXUS

C8

T15 terminal branches

C5

C6

C7

C8

5 Roots (v. rami)

3 Trunks6 Divisions

3 Cords5 terminal

Upper

Middle

LowerLat

3 ant.3 post.

Brachial Plexus

T15 terminal branches

LowerLat

Post

Medial

C5

C6

C7

C8

Small “non-terminal” Branches of the Brachial Plexus

dorsal scapular n.

n. to subclavius

suprascapular n.

lateral pectoral n.

SupraclavicularBranches

InfraclavicularBranches

C8

T1

medial pectoral n.

long thoracic

thoracodorsal n.

Lower and uppersubscapular nn.

medial cutaneous n. of the armmedial cutaneous n. of the forearm

SST

RA

Erb’s (Erb-Duchenne) Palsy

Obstetrical traumaMotorcycle accident

damage to upper part of brachial plexus

Upper Brachial Plexus C5 / C6 / C7

part of brachial plexus

“Waiter’s tip” position (arm adducted and internally rotated, forearm pronated and extended at elbow, +/- wrist flexed)

Upper Brachial Plexus C5 / C6 / C7

Lower brachial plexus C8 / T1

Klumpke’s (Klumpke-Dejerine) Palsy

Lower brachial plexus C8 / T1Cervical rib may be underlying causeKlumpke’s

(Klumpke-Dejerine) Palsy

Lower brachial plexus C8 / T1 Loss of intrinsic hand muscles (both ulnar and median)

“Ape Hand” clawing of fingers with flattening (atrophy) of thenar eminence

VENOUS DRAINAGE

Subclavian vein

Brachial vein

Cephalic vein

Median cubital vein

Axillary nodes

Basilic vein

Lymphatic vessels

Cubital (epitrochlear)

nodes

UL

Lateral Nodes (humeral)

Central Nodes

Apical Nodes

ULPosterior Nodes (scapular)

Parasternal Nodes

Anterior Nodes (pectoral)

Lymphedema following mastectomy

Lymph Drainage of the Breast

~75% to axillary nodes

~20% to ipsilateral parasternal nodes

Small % to contralateral parasternal nodesparasternal nodes

Lymphangitis - thumb/hand infectionLymphangitis - thumb/hand infection