The Axilla, Brachial Plexus and Arm

Question 1

The axilla is divided into 3 parts. What is the 1st branch of the axilla.

Answer 1

Superior thoracic artery

Question 2

In the 2nd part of the axilla what are the 2 branches

Answer 2

Thoraco-acromial
Lateral thoracic artery

Question 3

In the 3rd part of the axilla what are the 3 branches

Answer 3

subscapular artery
ant. circumflex humeral artery
post. circumflex humeral artery

Question 4

List the 5 groups of spinal nerves

Answer 4

8 Cervical
12 Thoracic (T1-T12)
5 Lumbar (L1-L5)
5 Sacral (S1-S5)
1 Coccygeal (Co1)

Question 5

What is the brachial plexus

Answer 5

network of nerves that controls muscle movements and sensations in the upper limb

Question 6

What are the 5 components of the brachial plexus

Answer 6

Roots, Trunks, Cords, Divisions, Branches

Question 7

Which spinal nerves form the brachial plexus

Answer 7

Brachial plexus is formed by the union of anterior rami C5, C6, C7, C8, T1

Question 8

What structure is innervated by the dorsal scapular

Answer 8

rhomboids, occasionally supplies the levator scapulae

Question 9

what structure is innervated by the long thoracic

Answer 9

serratus anterior

Question 10

what structure is innervated by the suprascapular nerve

Answer 10

supraspinatus and infraspinatus
glenohumeral joint

Question 11

what structure is innervated by the nerve to subclavius

Answer 11

subclavius and sternoclavicular joint

Question 12

Origin of biceps brachii

Answer 12

short head - tip of the coracoid process of scapula
long head - supraglenoid tubercle of scapula

Question 13

insertion of biceps brachii

Answer 13

radial tuberosity and fascia of forearm via bicipital aponeurosis

Question 14

innervation of biceps brachii

Answer 14

Musculocutaneous
nerve
C5,C6,C7

Question 15

action of biceps brachii

Answer 15

Supinates
forearm
* Flexes forearm
when supinated
* Short head
resists dislocation
of shoulder

Question 16

origin of coraco-brachialis

Answer 16

tip of coracoid process
of scapula

Question 17

insertion of caraco-brachialis

Answer 17

Middle third of medial
surface of humerus

Question 18

innervation of coraco-brachialis

Answer 18

Musculocutaneous
nerve
C5,C6,C7

Question 19

action of caraco-brachialis

Answer 19

Helps flex and
adduct the arm
* Resists
dislocation of arm

Question 20

origin of brachialis

Answer 20

Distal half of anterior
surface of humerus

Question 21

insertion of brachialis

Answer 21

Coronoid process and
tuberosity of ulna

Question 22

innervation of brachialis

Answer 22

Musculocutaneous
nerve (C5,C6) and
radial nerve (C5,C7)

Question 23

action of brachialis

Answer 23

Flexes forearm in
all positions

Question 24

origin or triceps brachii

Answer 24

Long head- infraglenoid
tubercle of scapula
* Lateral head- posterior
surface of humerus, superior
to radial groove
* Medial head- posterior
surface of humerus, inferior
to radial groove

Question 25

insertion of triceps brachii

Answer 25

Proximal end of
olecranon of ulna and
fascia of forearm

Question 26

innervation of triceps brachii

Answer 26

Radial nerve
C6,C7,C8

Question 27

action of triceps brachii

Answer 27

Chief extensor of
forearm
* Long head
resists
dislocation of
humerus
* Important during
adduction

Question 28

origin of anconeus

Answer 28

Lateral epicondyle of humerus

Question 29

insertion of anconeus

Answer 29

Lateral surface of
olecranon and superior
part of posterior surface
of ulnar

Question 30

innervation of anconeus

Answer 30

Radial nerve
C7,C8,T1

Question 31

action of anconeus

Answer 31

Assists triceps in
extending
forearm
* Stabilizes elbow
joint
* May abduct ulnar
during pronation

Question 32

does injury to the axilla lead to complete loss of innervation to triceps

Answer 32

True

Question 33

why is there incomplete loss of innervation to triceps when the radial nerve has been injured?

Answer 33

branch to the long head of the triceps is in the axilla

Question 34

Origin of brachial artery

Answer 34

Direct continuation of axillary artery at lower border of teres major

Question 35

end of the brachial artery

Answer 35

Neck of radius medial to biceps tendon where it divides into radial and ulnar arteries

Question 36

what are the medial branches of the brachial artery?

Answer 36

profunda brachii
superior ulnar collateral artery
inferior ulnar collateral artery

Question 37

What branches does the profunda brachii divide into?

Answer 37

middle and radial collateral arteries

Question 38

Which arteries does the superior ulnar collateral artery anastomose with?

Answer 38

the posterior ulna recurrent artery and inferior
ulnar collateral artery

Question 39

Which arteries does the inferior ulnar collateral artery anastomose with?

Answer 39

the anterior ulna recurrent artery

Question 40

What is the lateral branches of the brachial artery

Answer 40

the humeral nutrient artery

Question 41

What are the superficial veins of the arm?

Answer 41

Cephalic and basilic veins

Question 42

What are the deep veins of the arm

Answer 42

Brachial vein begins at the elbow by union of the accompanying veins of the ulnar and radial arteries
* Ends by merging with the basilic vein to form the axillary vein

Question 43

the injury of the upper trunk of the brachial plexus results in what disease

Answer 43

erb-duchenne paralysis

Question 44

the injury of the lower trunk of the brachial plexus results in what disease

Answer 44

Klampke’s paralysis

Question 45

is the skin over the deltoid muscle innervated by the branch of the axillary nerve

Answer 45

True