Upper limb 1: Brachial plexus

Question 1

The brachial plexus is formed from which ventral rami?

Answer 1

C5 - T1

Question 2

The brachial plexus emerges from between which 2 muscles?

Answer 2

Scalenus anterior

Scalenus medius

Question 3

The cords of the brachial plexus are wrapped around what?

Answer 3

Axillary artery

Question 4

Compression of the interscalene groove can result in which pathology?

Answer 4

Thoracic outlet syndrome

Question 5

Which muscle is a useful landmark to determine where the important structure in the axilla are positioned?

Answer 5

Coracobrachialis

Question 6

What is the brachial plexus wrapped in?

Answer 6

Axillary sheath

Question 7

The axillary sheath connects to a fascial space which surrounds what?

Answer 7

Vertebral column

Question 8

The axillary nerve is associated with which anatomical part of the humerus?

With which artery?

Answer 8

Neck of the humerus

Posterior circumflex humoral artery

Question 9

The radial nerve is associated with which bony landmark of the humerus?

With which artery?

Answer 9

Spiral groove (posterior)

Profunda brachia artery

Question 10

The median nerve is associated with which artery?

Answer 10

Brachial artery

Question 11

What are the 5 parts the brachial plexus can be divided into?

Answer 11

Roots
Trunks
Divisions
Cords
Branches

Question 12

Which 2 ventral rami form the upper trunk of the brachial plexus?

Answer 12

C5 + C6

Question 13

Which ventral rami forms the middle trunk of the brachial plexus?

Answer 13

C7

Question 14

Which 2 ventral rami form the lower trunk of the brachial plexus?

Answer 14

C8 + T1

Question 15

What are the 2 divisions of the brachial plexus?

Answer 15

Anterior
Posterior

Question 16

What are the 3 cords of the brachial plexus?

Answer 16

Lateral
Posterior
Medial

Question 17

What are the 5 main branches of the brachial plexus?

Answer 17

Musculocutaneous nerve
Median nerve
Radial nerve
Ulnar nerve
Axillary nerve

Question 18

Which 3 nerves form the ‘M’ shape at the end of the brachial plexus?

Answer 18

Musculocutaneous
Median
Ulnar

Question 19

The radial nerve carries which nerve rami?

Answer 19

C5 - T1 (all)

Question 20

Which 2 rami is brachioradialis innervated by?

Answer 20

C5 + C6

Question 21

Which 2 rami are the triceps innervated by?

Answer 21

C7 + C8

Question 22

Which part of the brachial plexus is most commonly involved in thoracic outlet syndrome?

Answer 22

Lower trunk

Question 23

A lung apex tumour is most likely to compress which root of the brachial plexus?

Answer 23

T1

Question 24

Which part of the brachial plexus is damaged in Erb’s palsy?

Answer 24

C5 / C6 roots / upper trunk

Question 25

Which symptoms would you get with Erb's palsy?

Answer 25

Medially rotated shoulder Pronated forearm Flexed wrist Wasting of deltoid and anterior arm C5 + C6 sensory loss

Question 26

What are the 5 main nerve branches which are formed mainly from C5 + C6 roots?

Answer 26

Dorsal scapular nerve Suprascapular nerve Lateral pectoral nerve Musculocutaneous nerve Axillary nerve

Question 27

Damage to which nerve would limit lateral shoulder rotation?

Answer 27

Suprascapular nerve

Question 28

Damage to which nerve would weaken medial shoulder rotation + adduction?

Answer 28

Lateral pectoral nerve

Question 29

Damage to which nerve would weaken the anterior compartment of the arm?

Answer 29

Musculocutaneous nerve

Question 30

Damage to which nerve would weaken deltoids + teres minor?

Answer 30

Axillary nerve

Question 31

Which part of the brachial plexus is damaged in Klumpke's palsy?

Answer 31

C8 / T1 roots / lower trunk

Question 32

Which symptoms would you get with Klumpke's palsy?

Answer 32

Wasting of the small muscles of the hand Clawing of digit 2 to digit 5 Changed resting position of the thumb C8 + T1 sensory loss

Question 33

List 3 ways the median nerve is most likely to be damaged.

Answer 33

Laceration to the medial arm or anterior wrist Brachial artery aneurysm Carpal tunnel syndrome

Question 34

List 2 ways the axillary nerve is most likely to be damaged.

Answer 34

Dislocation of the shoulder Fracture of surgical neck of the humerus

Question 35

List 3 ways the radial nerve is most likely to be damaged.

Answer 35

Crutches Fracture of humeral shaft through spiral groove Dislocated head / neck of radius (mainly affect posterior interosseous branch)

Question 36

List 3 ways the ulnar nerve is most likely to be damaged.

Answer 36

Fracture of medial humeral condyle Cubital tunnel syndrome Penetrating injury to medial side of anterior wrist