Week 11 Content Flashcards
What makes up the apex of the axilla?
AKA the inlet of the axilla
clavicle, superior border of scapula, first rib
What make up the medial, posterior, lateral, and anterior walls of the axilla?
medial- serratus anterior
posterior- subscapularis, teres major, latissimus dorsi
lateral- humerus, coracobrachialis long head of biceps
anterior- pectoralis major and minor
Where does the long thoracic nerve originate?
from roots of C5, C6, C7 before the formation of the superior, middle, and inferior trunks of the brachial plexus
Long thoracic nerve passes posterior to which muscle?
middle scalene (hides it)
If the long thoracic nerve is damaged, what happens to movement of the arm?
innervates the SA, which assists the scapula in raising the arm by keeping it next to the thoracic wall (pulling the scapula medially and inferiorly). therefore, damage to the nerve causes the SA to elevate away from the thoracic wall, resulting in:
- trouble raising the arm to the level of the shoulder
- winging of the scapula when the arm is pushed forward
What nerves form the brachial plexus?
ventral primary rami of spinal nerves C5-T1
What is the order of organization of sections of the brachial plexus?
roots (ventral rami) trunks divisions cords terminal branches (peripheral nerves)
How many nerves branch from the divisions of the brachial plexus?
none. branches only come off of the roots, trunks, and cords
Name the muscles supplied by the musculocutaneous nerve.
coracbrachialis
biceps brachii
greater part of the brachialis
What are the terminal branches of the lateral, posterior, and medial cords?
lateral cord- musculocutaneous n. and some of median n.
posterior cord- radial n.
medial cord- ulnar n. and some of median n.
Which muscle divides the axillary artery into 3 parts? Describe the parts and the branches of each.
pec minor
part 1- medial (superior) to pec minor; has 1 branch (superior thoracic a.)
part 2- posterior to pec minor; has 2 branches (thoraco-acromial a. and lateral thoracic a.)
part 3- lateral (inferior) to pec minor; has 3 branches (subscapular a., anterior circumflex humeral a., posterior circumflex humeral a.)
How do the pronator muscles of the forearm accomplish pronation?
when they contract, the radius rotates at the elbow and the distal radius crosses over the ulna. they are assisted by the anconeus muscle posteriorly
Name the contents of the carpal tunnel.
flexor digitorum superficialis tendons flexor digitorum profundus tendons flexor pollicis longus tendon flexor carpi radialis tendon median n.
Name the contents of the cubital fossa from lateral to medial.
TAN
Tendon of biceps brachii
Artery (brachial a. and accompanying vein)
Nerve (medial n.)
What is the clinical importance of the cubital fossa?
like other flexion surfaces of large joints (groin, popliteal fossa, armpit, anterior neck), it is an area where blood vessels and nerves pass relatively superficially, and with an increased amount of lymph nodes.
the area just superficial to the cubital fossa is often used for venous access (phlebotomy) in procedures such as injections, obtaining samples for blood tests, or the insertion of a peripherally inserted central catheter (PICC line)
What is the historical significance of the cubital fossa?
when blood-letting was practiced, the bicipital aponeurosis was known as the “grade of God” tendon because it protected the more important contents of the fossa (the brachial artery and the median n.)
Describe the fascial compartments of the brachium.
arm is enclosed in a sheath of fascia known as the brachial fascia, which is continuous with the fascia of the axilla and the fascia of the forearm
brachial fascia gives rise to the medial and lateral intermuscular septa that divide the arm into anterior and posterior compartments
Describe OINA for biceps brachii.
O- supraglenoid tubercle of scapula (long head) and coracoid process of scapula (short head)
I- tuberosity of the radius and bicipital aponeurosis
N- musculocutaneous n.
A- forearm flexion and supination
Describe OINA for coracobrachialis.
O- coracoid process of the scapula
I- middle third of the medial side of the humerus
N- musculocutaneous n.
A- shoulder/arm flexion and adduction
Describe OINA for brachialis.
O- distal half of anterior surface of humerus
I- coronoid process and tuberosity of the ulna
N- musculocutaneous n.
A- forearm flexion
Describe OINA for triceps brachii.
O- infraglenoid tubercle (long head), posterior humerus inferior to spiral groove (medial head), posterior humerus superior to the spiral groove (lateral head)
I- olecranon process of the ulna
N- radial n.
A- forearm extension
Describe OINA for anconeus.
not considered part of the posterior compartment
O- lateral epicondyle of humerus
I- lateral surface of the olecranon process and posterior surface of the ulna
N- radial n.
A- forearm extension
Describe the location of the musculocutaneous nerve and what it supplies.
arises from the lateral cord of the brachial plexus and supplies the muscles of the anterior brachium
Describe the location of the radial nerve and what it supplies.
arises from the posterior cord of the brachial plexus and supplies the posterior muscles of the brachium and continues into the forearm
Describe the location of the brachial artery, what it branches into, and what it supplies.
The brachial artery comes off of the axillary artery and gives rise to the profunda brachii artery, which travels to the posterior brachium with the radial nerve to supply the posterior compartment
accompanied by 2 brachial veins
Describe the venous drainage of the brachium.
These are 2 superficial veins that are located along the lateral and medial
borders of the arm
- Cephalic- runs along the anterior lateral surface of the biceps and empties into
the axillary vein near the deltopectoral triangle - Basilic- runs along the inferior, medial surface. It enters deep to the brachial
fascia at the middle of the arm and becomes the axillary vein - Median cubital vein- communication of the cephalic and basilic in the cubital
fossa
Describe the boundaries of the cubital fossa.
Superior - imaginary line between the epicondyles of the humerus
Lateral - brachialradialis
Medial - pronator teres
Floor - Medial – Brachialis
Lateral – supinator
Roof - cubital fasciaDescribe the contents of the superficial layer of the cubital fossa.
Basilic vein
Cephalic vein
Median cubital vein
Bicipital aponeurosis
Describe the contents of the deep layer of the cubital fossa.
T – Tendon of the Biceps Brachii Lateral
A – Brachial artery
N – Median nerve Medial
Also the radial and ulnar nerves can be found nearby
Describe OINA for supinator.
O- lateral epicondyle of the humerus
I- lateral, posterior, and anterior surfaces of the proximal third of the radius
N- deep branch of the radial n.
A- supinates the forearm
Describe OINA for brachioradialis.
O- proximal 2/3 of the lateral supracondylar ridge of humerus
I- lateral surface of the distal end of the radius
N- radial n.
A- forearm flexion
Describe OINA for pronator teres.
O – Medial epicondyle of the humerus and coronoid process of the ulna
I – Middle of lateral surface of the radius
N – Median n.
A – pronates and flexes forearm
Describe OINA for flexor carpi radialis.
O – Medial epicondyle of humerus
I – base of the second metacarpal bone
N – Median n.
A – Flexes and radially deviates hand
Describe OINA for palmaris longus.
O – Medial epicondyle of humerus
I – flexor retinaculum and palmar aponeurosis
N – Median n.
A – flexes hand
Describe OINA for flexor digitorum superficialis.
O – medial epicondyle of the humerus, coronoid process of the ulna and
the anterior border of the radius
I – Bodies of the middle phalanges of the medial four digits
N – Median n.
A – flexes the middle phalanges of the medial four digits, the proximal
phalanges and hand
Describe OINA for flexor carpi ulnaris.
O – Medial epicondyle of humerus, olecranon and ulna
I – Pisiform, hook of the hamate and 5th metacarpal
N – Ulnar n.
A – flexes hand, ulnar deviates hand
Describe OINA for flexor digitorum profundus.
O – Proximal three-fourths of medial and anterior surface of the ulna
and interosseous membrane
I – base of the distal phalanges of the medial four digits
N – Medial part is ulnar Lateral part is median
A – flexes the distal phalanges of the medial four digits
Describe OINA for flexor pollicis longus.
O – Anterior surface of the radius and interosseous membrane
I – base of the distal phalanx of the thumb
N – Anterior interosseous n.
A – Flexes phalanges of thumb
Describe OINA for pronator quadratus.
O – Distal, anterior surface of ulna
I – Distal, anterior surface of the radius
N – Anterior interosseous nerve
A – Pronates the forearm
Describe the location of the median nerve and what it supplies.
it enters the forearm via the cubital fossa and travels along the lateral aspect of
the anterior forearm.
It gives off the anterior interosseous nerve, which runs deep to the superficial
muscle of the forearm. It innervates the deep muscles of the forearm.
Describe the location of the ulnar nerve and what it supplies.
Passes posterior to the medial epicondyle of the humerus and enters the
forearm medial to the flexor carpi ulnaris
It dives deep and runs with the ulnar artery to the wrist
Describe the radial nerve and what it supplies.
It enters the forearm by passing anteriorly over the lateral epicondyle of the
humerus.
Once in the forearm it divides into superficial and deep branches
Superficial branch is responsible for sensory, deep branch is responsible for
motor and joint innervation
What does the brachial artery branch into?
branches into radial artery and ulnar artery in the inferior aspect of the cubital fossa
Describe the radial artery including its location and branches.
It runs along the lateral aspect of the anterior surface of the forearm
It is the common site for measuring pulse rate
It terminates in the hand as part of the palmar arch
Radial recurrent artery - arises from the radial artery just distal to the brachial
artery. It ascends the arm to anastomose with the radial collateral artery (a
branch of the profunda brachii)
Describe the ulnar artery, including its location and branches.
It arises in the inferior cubital fossa and descends the anterior, medial aspect of
the forearm and enters the hand to form part of the palmar arch
it gives off the following branches:
- Anterior ulnar recurrent artery- it arises just inferior to the elbow and ascends
to anastomose with the inferior ulnar collateral artery - Posterior ulnar recurrent artery- it arises just distal to the anterior ulnar
recurrent and ascends posteriorly to anastomose with the superior
ulnar collateral artery - Common interosseous artery, which divides into anterior and posterior interosseous arteries
- Anterior interosseous artery - runs deep on the anterior surface of the
interosseous membrane supplying structures of the deep forearm
- Posterior interosseous artery- passes posterior to the interosseous
membrane and supplies structures in the posterior compartment of the forearm
What are the contents of the axilla?
axillary vessels and their branches
parts of the brachial plexus and their branches
What forms each trunk of the brachial plexus?
upper trunk is formed by rami C5 and C6
middle trunk is formed by rami C7
lower trunk is formed by C8 and T1
The trunks of the brachial plexus divide into what?
3 anterior divisions and 3 posterior divisions
What forms each cord of the brachial plexus?
posterior cord- formed by posterior divisions
lateral cord- formed by anterior division of the upper trunk and anterior division of the middle trunk
medial cord- formed by the anterior division of the lower trunk
Cords are named according to what?
their relationship with the axillary artery
What terminal branches do each cord give off?
lateral cord- muculocutaneous n. and lateral root of the median n.
medial cord- ulnar n. and medial root of the median n.
posterior cord- axillary n. and radial n.
List the branches coming off of the ventral primary rami.
phrenic nerve - C3, C4, C5
dorsal scapular nerve- C5
long thoracic nerve- C5, C6, C7
List the branches coming off of the trunk of the brachial plexus.
suprascapular nerve- upper trunk
nerve to subclavius- upper trunk
List the branches off of each cord of the brachial plexus.
medial cord- medial pectoral n, medial brachial cutaneous, medial antebrachial cutaneous
lateral cord- lateral pectoral n
posterior cord- upper subscapular n, lower subscapular n, thoracodorsal n
Describe part 1 of the axillary artery.
from the first rib to the superior border of the pec minor
gives off 1 branch - superior thoracic artery - which supplies the first 2 intercostal spaces
Describe Part 2 of the axillary artery.
from the superior border of the pec minor to the inferior border of the pec minor
gives off 2 arteries:
- thoracoacromial artery, which divides into clavicle, pectoral, acromial, and deltoid branches
- lateral thoracic artery, which supplies the anterolateral thoracic wall
Describe Part 3 of the axillary artery.
from the inferior end of the pec minor to the superior border of the teres major.
gives rise to 3 arteries:
- subscapular artery, the largest branch that passes posteriorly and divides into circiumflex scapular artery and thoracodorsal artery. circumflex scapular artery anastomoses with the suprascapular artery in the infraspinous fossa. thoracodorsal descends the posterior wall to the latissimus dorsi
- anterior humeral circumflex artery
- posterior humeral circumflex artery, which passes around the surgical neck of the humerus with the anterior humeral circumflex artery
The axillary artery becomes what as it passes by which muscle inferior to the pec minor?
it becomes the brachial artery as it passes the teres major
