Nerve and Blood Supply to the Upper Limb

Question 1

Name some of the common causes of brachial plexus injury

Answer 1

Disease, stretching or wounds to the lateral cervical or axilla regions

Question 2

What is superior brachial plexus injury known as?

Answer 2

Erb-Duchenne palsy

Question 3

What is inferior brachial plexus injury known as?

Answer 3

Klumpke palsy

Question 4

What is meant by a superior brachial plexus injury?

Answer 4

Involves damage to C5-C6 nerves

Question 5

What is meant by an inferior brachial plexus injury?

Answer 5

Involves damage to C8-T1 nerves

Question 6

What are the consequences of a superior brachial plexus injury and why?

Answer 6

Loss of sensation of lateral aspect of arm (C5-C6 dermatome) and paralysis of deltoid, biceps and brachialis

Question 7

How will an individual with Erb-Duchenne palsy present?

Answer 7

limb will be adducted to the shoulder, medially rotated and elbow extended

Question 8

Name the two nerves from the posterior cord of the brachial plexus

Answer 8

Axillary and radial nerves

Question 9

How will an individual with Klumpke palsy present?

Answer 9

hand appears clawed due to ulnar nerve palsy

Question 10

Name the three nerves from the anterior cord of the brachial plexus

Answer 10

Median, musculocutaneous and ulnar

Question 11

Describe the motor and sensory innervation of the axillary nerve

Answer 11

MOTOR: shortest terminal branch and goes under shoulder joint and supplies deltoid muscle
SENSORY: lateral arm

Question 12

How can damage to the axillary nerve be caused and how would the patient present?

Answer 12

CAUSE: dislocated shoulder or fracture of humerus neck
SYMPTOMS: paralysis of deltoid and loss of sensation over lateral arm

Question 13

Describe the sensory and motor innervation of the radial nerve

Answer 13

MOTOR: all of the extensor muscles in posterior forearm
SENSORY: between thumb and index finger on dorsum of the hand

Question 14

How can damage to the radial nerve be caused and how would the patient present?

Answer 14

CAUSE: fractures to humerus midshaft (as nerve runs right next to the humerus in a groove)
SYMPTOMS: weakened elbow extension and wrist drop and loss of sensation in web between thumb and index finger

Question 15

Describe the sensory and motor innervation of the ulnar nerve

Answer 15

MOTOR: intrinsic muscles of the hand
SENSORY: little finger and medial palm

Question 16

How can damage to the ulnar nerve be caused and how would the patient present?

Answer 16

CAUSE: fracture to medial epicondyle of humerus
SYMPTOMS: loss of sensation in little finger and medial palm

Question 17

Describe the sensory and motor innervation of the median nerve

Answer 17

SENSORY: sensation to thumb and index finger
MOTOR: digit flexors and muscles moving thumb

Question 18

How can damage to the median nerve be caused and how would the patient present?

Answer 18

CAUSE: supracondylar fractures and compression/laceration of the wrist
SYMPTOMS: paralysis of digit flexors and muscles moving thumb, and long-term caused atrophy of thenar muscles, giving ‘ape-hand’, also a loss of sensation in thumb and index finger

Question 19

What movement would you use to test the radial nerve?

Answer 19

thumbs up (if can’t there is damage)

Question 20

What movement would you use to test the ulnar nerve?

Answer 20

peace out sign (claw hand usually if damage, so can’t extend fingers)

Question 21

What movement would you use to test the median nerve?

Answer 21

‘fist-bump’ action as if there is damage will not be able to flex the fingers in this way

Question 22

Where is the brachial plexus palpable?

Answer 22

Superior border of the clavicle

Question 23

State the nerve roots of the brachial plexus

Answer 23

C5-T1 mainly, potential for C4 and T2

Question 24

Where is the C4 dermatome?

Answer 24

top of shoulder

Question 25

Where is the C5 dermatome?

Answer 25

lateral arm

Question 26

Where is the C6 dermatome?

Answer 26

lateral forearm and thumb

Question 27

Where is the C7 dermatome?

Answer 27

middle finger

Question 28

Where is the C8 dermatome?

Answer 28

little finger

Question 29

Where is the T1 dermatome?

Answer 29

strip of skin of medial forearm up to chest

Question 30

What are the different subdivisions of the brachial plexus?

Answer 30

Nerve roots, trunks, divisions, cords, terminal branches

Question 31

Where can you locate the radial pulse?

Answer 31

lateral to the tendon of the flexor carpi radialis muscle

Question 32

Where can you locate the ulnar pulse?

Answer 32

lateral to tendon of the flexor carpi ulnaris muscle (deeper so more difficult to find and lies under pisiform)

Question 33

Where can you locate the brachial pulse?

Answer 33

medially to the distal tendon of the biceps brachii

Question 34

What type of blood supply is present around joints?

Answer 34

Collateral

Question 35

Describe the arterial blood supply to the upper limb

Answer 35

The subclavian artery becomes the axillary artery as it passes through the axilla. Then the humeral circumflex branches off from the axillary artery. The axillar artery then branches into the deep brachial artery, the brachial artery and the ulnar collateral arteries (medial). The brachial and deep brachial then reconnect to form the radial artery. The ulnar nerve then branches from the brachial artery and travels medially . These then form the deep palmar arch, superficial palmar arch and digital arteries.

Question 36

What is compartment syndrome?

Answer 36

A condition resulting from increased pressure within a confined body space (especially of the leg or forearm)

Question 37

Describe the venous drainage of the upper limb

Answer 37

The right subclavian vein splits into the cephalic (lateral) and axillary veins (medial). The axillary vein then splits into the brachial vein (middle of arm) and basilica vein (medial). The median cubital vein reconnects the basilica vein and cephalic veins to continue the cephalic vein. The basilica vein continues to the hand. The brachial vein splits into the radial and ulnar veins and goes on to supply the deep plasma veins, superficial palmar and digital veins.

Question 38

What are the superficial veins of the arm?

Answer 38

basilic vein, cephalic vein and median cubital vein