Dissection: Upper Limb

Question 1

Which muscle retracts the scapula?

Answer 1

Rhomboids

Question 2

Which muscle protracts the scapula?

Answer 2

Serratus anterior

Question 3

Which muscles elevate the scapula?

Answer 3

Levator scapulae and upper trapezius

Question 4

Which muscles depress the scapula?

Answer 4

Latissimus dorsi and lower trapezius

Question 5

What is the nerve supply to the trapezius?

Answer 5

CN XI (spinal accessory nerve)

Question 6

What is the nerve supply to the levator scapulae and rhomboids?

Answer 6

Dorsal scapulae nerve (C3,C4,C5)

Question 7

What is the nerve supply to serratus anterior?

Answer 7

Long thoracic nerve

Question 8

What is the nerve supply to teres major?

Answer 8

Subscapular nerve

Question 9

What is the nerve supply to teres minor?

Answer 9

Axillary nerve

Question 10

What is the nerve supply to subscapularis?

Answer 10

Subscapular nerve

Question 11

What is the nerve supply to supraspinatus and infraspinatus?

Answer 11

Suprascapular nerve

Question 12

What are the boundaries of the axilla?

Answer 12

Anterior = pectoralis minor and major
Posterior = Subscapularis, latissimus dorsi and teres major
Medial = serratus anterior and rib cage
Lateral = bicipital groove of humerus

Question 13

Name the 5 terminal branches of the brachial plexus

Answer 13

Axillary, radial, musculocutaneous, median, ulnar

Question 14

Name the three cords of the brachial plexus

Answer 14

Posterior, lateral and medial

Question 15

Which nerves stem from the posterior cord of the brachial plexus?

Answer 15

Axillary and radial

Question 16

Which nerves stem from the lateral cord of the brachial plexus?

Answer 16

Musculocutaneous (and gives rise to median)

Question 17

Which nerves stem from the medial cord of the brachial plexus?

Answer 17

Median nerve (with branches from lateral cord also) and ulnar nerve

Question 18

Which nerve roots supply the musculocutaneous nerve?

Answer 18

C5,6,7

Question 19

What does the musculocutaneous nerve innervate?

Answer 19

Motor = brachialis, biceps brachialis and coracobrachialis (BBC - flexors)
Sensory: lateral forearm

Question 20

How is the musculocutaneous nerve damaged, and what are the symptoms?

Answer 20

How? Deep laceration (rare)

Signs = paralysis of arm flexors

Question 21

Which nerve roots supply the median nerve?

Answer 21

C5-T1

Question 22

What does the median nerve innervate?

Answer 22

Motor: Flexors of forearm (except for flexor carpi ulnaris and the ulnar 1/2 of flexor digitorum profundus), lateral (radial) 2 lumbricals and thenar (thumb) muscles
Sensory: First radial 3 1/2 digits on palm of hand and tips of first radial 3 1/2 digits on dorsal surface

Question 23

How may the median nerve be damaged?

Answer 23

Supracondylar fracture OR carpal tunnel compression

Question 24

What are the symptoms of median nerve damage?

Answer 24

Hand of benediction whereby, when asked to make a fist, the individual can only flex the first 1 1/2 ulnar digits (involves flexion of DIP and PIP by the lumbricals which has lost medial innervation)

Question 25

Which nerve roots supply the ulnar nerve?

Answer 25

C8-T1

Question 26

What does the ulnar nerve innervate?

Answer 26

Motor: FCU, FDP (ulnar half) and all hand muscles except thenar and 2 lateral lumbricals Sensory: to dorsal and palmar sides of first 1/2 ulnar digits and associated palm

Question 27

How may the ulnar nerve be damaged?

Answer 27

Medial epicondyle fracture OR deep wrist laceration

Question 28

What are the symptoms of ulnar nerve damage?

Answer 28

Develop ulnar claw whereby the first 2 ulnar digits extend at the MCP and flex at the DIP and PIP

Question 29

Which nerve roots supply the axillary nerve?

Answer 29

C5,C6

Question 30

What does the axillary nerve innervate?

Answer 30

Motor: deltoid and teres minor Sensory: regimental patch on shoulder

Question 31

How may the axillary nerve be damaged?

Answer 31

Dislocated shoulder or fracture of humeral neck

Question 32

What are the symptoms of axillary nerve damage?

Answer 32

Inability to abduct shoulder (greater than 10 degrees - done by supraspinatus) due to paralysis of deltoid

Question 33

Which nerve roots supply the radial nerve?

Answer 33

C5-T1

Question 34

What does the radial nerve innervate?

Answer 34

Motor: all extensor muscles of arm and forearm (posterior compartment) Sensory: Posterior aspect of arm and forearm and the 1st dorsal interosseous web

Question 35

How may the radial nerve be damaged?

Answer 35

Midshaft fracture to the humerus (travels in spiral groove)

Question 36

What are the symptoms of radial nerve damage?

Answer 36

Wrist drop - due to loss of innervation to extensors of the forearm

Question 37

What are the boundaries of the deltopectoral triangle?

Answer 37

lateral border of pectoralis major (clavicular head), the clavicle and the anterior deltoid muscle

Question 38

What are the contents of the deltopectoral triangle?

Answer 38

Cephalic vein, subclavian artery, subclavian vein

Question 39

What are the boundaries of the quadrangular space?

Answer 39

``` Superior = teres minor Inferior = teres major Lateral = humerus Medial = long head of triceps ```

Question 40

What are the contents of the quadrangular space?

Answer 40

Axillary nerve and posterior circumflex (humerus) artery and vein

Question 41

What are the boundaries of the triangular interval?

Answer 41

``` Superior = teres major Medial = long head of triceps Lateral = humerus ```

Question 42

What are the contents of the triangular interval?

Answer 42

Radial nerve and profunda brachii artery

Question 43

What are the boundaries of the cubital fossa?

Answer 43

``` Lateral = brachioradialis Medial = pronator teres Superior = imaginary line between 2 epicondyles Roof = antebrachial fascia and bicipital aponeurosis Floor = brachialis and supinator ```

Question 44

What are the contents of the cubital fossa?

Answer 44

Radial nerve, medial nerve, biceps tendon, brachial artery