Axilla and Neurovascular Input to the Upper Limb

Question 1

what is the axilla?

Answer 1

• the axilla is a pyramidal space below the shoulder joint.
• it provides a passageway for vessels and nerves going to and from the upper limb.

Question 2

the anterior wall of axilla is formed by?

Answer 2

• pectoralis (major and minor) muscle
• subclavius muscle

Question 3

the posterior wall of the axilla is formed by which 3 muscles?

Answer 3

• subscapularis
• teres major
• lattisimus dorsi

Question 4

the medial wall of the axilla is formed by?

Answer 4

• thoracic wall
• serratus anterior muscle

Question 5

lateral wall of the axilla is formed by?

Answer 5

• intertubercular groove of ther humerus

Question 6

Answer 6

Question 7

the axillary artery is the continuation of which artery?

Answer 7

subclavian artery

Question 8

at what anatomical point does the axillary artery begin?

Answer 8

outer border of the first rib

Question 9

the axillary artery continues beyond the axilla as which vessel?

Answer 9

brachial artery

Question 10

at what anatomical point does the axillary artery turn into the brachial artery?

Answer 10

axillary becomes brachial at inferior border of teres major tendon

Question 11

describe the brachial plexus

Answer 11

The major network of nerves innervating the upper limb. It begins in the cervical region and extends into axilla.

Question 12

the brachial plexus is formed by the ventral rami of?

Answer 12

C5-T1
- these are the roots of the brachial plexus.

Question 13

which nerve roots form the upper trunk of the brachial plexus?

Answer 13

C5 & 6

Question 14

which roots of the brachial plexus contribute to the lower trunk?

Answer 14

C8-T1

Question 15

which root of the brachial plexus forms the middle trunk?

Answer 15

C7

Question 16

which artery and vein are the trunks of the brachial plexus closely related to?

Answer 16

axillary

Question 17

label the sub divisions of the brachial plexus

Answer 17

Question 18

Answer 18

Question 19

which muscles are affected in Erb’s palsy? They are supplied by the nerve roots C5-6.

musculocutaneous, axillary, suprascapular, and nerve to subclavius affec

Answer 19

• supraspinatus,
• infraspinatus,
• subclavius,
• biceps brachii,
• brachialis,
• coracobrachialis,
• deltoid and
• teres minor.

Question 20

injury to the lower trunk of the brachial plexus causes which condition? which muscles are involved?

Answer 20

• Klumpke’s palsy
• this mainly affects the intrinsic muscles of the hand (typically a claw hand), flexors muscles of the wrist and flexor muscles of the finger.

Question 21

list the 5 main terminal branches of the brachial plexus and which cord they originate from

Answer 21

1. radial nerve from posterior cord
2. axillary nerve from posterior cord
3. musculocutaneous nerve from lateral cord
4. ulnar nerve from medial cord
5. median nerve from both the lateral and medial cord

Question 22

Answer 22

Question 23

Answer 23

Question 24

Answer 24

Question 25

Answer 25

cephalic
basilic

Question 26

which large communicating vein shunts blood from the cephalic vein to the basilic vein?

Answer 26

median cubital vein

Question 27

describe the course of the cephalic vein

Answer 27

the cephalic vein ascend the arm on its lateral aspect, piercing the clavipectoral fascia draining into the axillary vein

Question 28

describe the course of the basilic vein

Answer 28

• the basilic vein ascends on the medial side of the arm, passing deep at the mid-humeral level and eventually becoming the axillary vein at the lower border of teres minor