Upper Limb

Question 1

What is the innervation of the trapezius muscle, and what is its effect on the shoulder girdle?

Answer 1

Innervated by CN XI

Elevates, depresses and retracts the scapula

Question 2

What is the innervation and function of the levator scapulae muscle?

Answer 2

Innervation is by dorsal scapular nerve and direct C3-C4 fibres

Action is to elevate the scapula

Question 3

What are Rhomboid Minor and Rhomboid Major innervated by?

Answer 3

The dorsal scapular nerve

Question 4

What nerve innervates the following muscles?

• Supraspinatus
• Infraspinatus
• Teres minor
• Subscapularis

Answer 4

Supraspinatus - suprascapular nerve

Infraspinatus - suprascapular nerve

Teres minor - axillary nerve

Subscapularis - upper and lower subscapular nerves

Question 5

What is the action of the following muscles?

• Supraspinatus
• Infraspinatus
• Teres minor
• Subscapularis

Answer 5

Supraspinatus - initiation of abduction of the arm

Infraspinatus - external rotation of the arm

Teres minor - external rotation of the arm

Subscapularis - internal rotation of the arm

Question 6

Where do the heads to biceps brachii originate?

Where does this muscle insert?

Answer 6

Long head - supraglenoid tubercle of scapula

Short head - coracoid process of scapula

Inserts into the radial tuberosity

Question 7

What three muscles are found in the anterior compartment of the arm?

What is the function of each?

What nerve supplies all of these muscles?

Answer 7

Biceps brachii (supination of forearm, and flexion of the arm at the shoulder and elbow)

Coracobrachialis (flexion of arm at shoulder)

Brachialis (flexion of arm at elbow)

All innervated by the musculocutaneous nerve

Question 8

Where do each of the heads of the tricep originate?

Where do they all insert?

Which nerve supplies this muscle?

Answer 8

Long head - infraglenoid tubercule of scapula

Medial head - posterior surface of humerus

Lateral head - posterior surface of humerus

All insert on the olecranon of the ulna

Innervated by the radial nerve

Question 9

What are the muscles of the superficial anterior compartment of the forearm?

What nerves supply them?

Answer 9

Pronator teres (median nerve)

Flexor carpi radialis (median nerve​)

Palmaris longus (median nerve​)

Flexor carpi ulnaris (ulnar nerve)

Question 10

What is the common flexor origin for all muscles in the superficial anterior compartment of the forearm?

Answer 10

The medial epicondyle of the humerus

Question 11

What muscle makes up the intermediate layer of the anterior compartment of the forearm?

What two structures pass between the two heads of this muscle?

What is this muscle’s action? What nerve supplies it?

Answer 11

Flexor digitorum superficialis

The median nerve and the ulnar artery pass between the two heads of this muscle

This muscle flexes the MCP joints (and PIP joints) of the medial 4 digits

Supplied by the median nerve

Question 12

What muscles make up the deep layer of the anterior compartment of the forearm? (3)

What is their nerve supply and function?

Answer 12

Flexor digitorum profundus -

• medial half (ulnar nerve)
• lateral half (median nerve)
• function - flexes DIP joints of medial 4 digits

​Flexor pollicis longus

• median nerve
• function - flexes IP joint of thumb

Pronator quadratus

• median nerve
• function - pronates forearm

Question 13

Which nerve innervates all of the thenar muscles?

Name these muscles

Answer 13

The median nerve

LOAF muscles

• Lumbricals (lateral 2)
• Opponens pollicis
• Adductor pollicis brevis
• Flexor pollicis brevis

Question 14

Where do all of the LOAF muscles originate? (3)

Answer 14

Flexor retinaculum

Scaphoid

Trapezium

Question 15

Which nerve innervates all of the hypothenar muscles?

Name these muscles

Answer 15

The deep branch of the ulnar nerve

(from lateral to medial)

Abductor digiti minimi

Flexor digiti minimi brevis (and opponens digiti minimi)

Question 16

Damage to what nerve and a resultant weakness in what muscle results in winging of the scapula?

Answer 16

Damage to the dorsal scapular nerve supplying serratus anterior

Question 17

The long thoracic nerve comes off of which spinal nerve roots?

Answer 17

C5, C6 and C7

Question 18

Contents of the carpal tunnel

Answer 18

9 tendons - 4 Flexor digitorum superficialis, 4 Flexor Digitorum profundus and 1 Flexor Pollicis longus

Median nerve

Question 19

A palsy of what nerve would present with a Hand of Benediction sign when trying to make a fist?

Answer 19

Median nerve palsy

Question 20

The interossei muscles ___ the fingers at the MCPs and ___ the fingers at the interphalangeal joints

Answer 20

Interossei muscles flex fingers at the MCPs and extend fingers at the IPJs

Question 21

What nerve supplies all of the interossei?

Which interossei mucles abduct the fingers and which adduct?

How many are there of each?

Answer 21

The ulnar nerve (deep branch) innervates all of the interossei

The dorsal interossei ABDUCT the fingers at the MCP joints (DAB). There are 4 dorsal interossei

The palmar interossei ADDUCT the fingers at the MCP joints (PAD). There are 3 palmar interossei

Question 22

What is the function of the lumbricals? How many are there?

Which nerve(s) innervate them?

Answer 22

Lumbricals link the flexor and extensor tendons for each digit, and there is one for each finger (4 total)

Innervation

• 2 lateral (lumbricals 1 and 2) - median nerve
• 2 medial (lumbricals 3 and 4) - ulnar nerve

Question 23

What muscles are found in the superficial posterior compartment of the forearm? (7)

What nerve innervates all of these muscles?

Answer 23

• Brachioradialis
• Extensor carpi radialis longus
• Extensor carpi radialis brevis
• Anconeus
• Extensor digitorum
• Extensor carpi ulnaris
• Extensor digiti minimi

All innervated by the radial nerve

Question 24

What muscles are found in the deep compartment of the forearm? (5)

What nerve innervates all of these muscles?

Answer 24

• Supinator
• Extensor pollicis brevis
• Abductor pollicis longus
• Extensor pollicis longus
• Extensor indices

Again, all innervated by the radial nerve

Question 25

Describe the arterial supply to the arm

Answer 25

Subclavian artery \> Brachial artery \> (splits) radial and ulnar arteries Radial and ulnar arteries from an anastomosis at the hands, creating the **superficial and deep palmar arches** From these arches come the **common digital arches**

Question 26

Describe the venous drainage of the upper limb

Answer 26

From the palm, the **dorsal venous network** drains into the cephalic and basilic veins Laterally - **cephalic vein** Medially - **basilic vein** Branch runs between these two at the flexion of the elbow called the **median cubital vein** The Basilic vein becomes the **Brachial vein** and is then joined by the cephalic vein to become the **axillary vein**, which then becomes the **subclavian vein**. The brachial vein is also joined by the **venae comitantes** (which accompany the brachial artery)

Question 27

Artery, vein and nerve supplying the anterior compartment of the arm

Answer 27

Artery - brachial Vein - brachial Nerve - musculocutaneous

Question 28

Artery, vein and nerve supplying the posterior compartment of the arm

Answer 28

Artery - profunda brachii Vein - profunda brachii Nerve - radial

Question 29

Artery, vein and nerve supplying the anterior compartment of the forearm

Answer 29

Artery - radial and ulnar Vein - venae comitantes Nerve - median

Question 30

Artery, vein and nerve supplying the posterior compartment of the forearm

Answer 30

Artery - interosseous Vein - venae comitantes Nerve - radial

Question 31

Artery, vein and nerve supplying the hand

Answer 31

Artery - deep and superficial palmar branches Vein - dorsal and palmar venous plexuses Nerve - ulnar (and median = LOAF)

Question 32

What nerves supply sensory innervation to the hand?

Answer 32

Median Radial Ulnar

Question 33

The function of what nerve needs to be assessed before releasing a patient that has dislocated their shoulder?

Answer 33

The **axillary nerve** (supplies teres minor and the deltoid)

Question 34

What makes up the borders of the quadrangular space? Which nerve passes through this space?

Answer 34

Horizontal borders - teres major and teres minor medial border - long head of the triceps lateral border - humerus Nerve - **axillary nerve**