Review of Anatomy of Upper Limb

Question 1

What is the upper limb divided into for descriptive purposes? (4)

Answer 1

Shoulder (between thorax and arm, includes pectoral girdle)
Arm (between shoulder and elbow)
Forearm (between elbow and wrist)
Hand (distal to wrists)

Question 2

What bones make up the shoulder? (3)

Answer 2

Clavicle, scapula and humerus

Question 3

What joints make up the shoulder? (3)

Answer 3

Sternoclavicular, acromoclavicular and glenohumeral

Question 4

What is the blood supply to the shoulder? (3)

Answer 4

Subclavian
Axillary
Brachial

Question 5

Where does the subclavian artery become the axillary artery?

When does it become brachial?

Answer 5

Lateral border 1st rib

Inferior border of teres major

Question 6

What is the venous drainage of the shoulder? (3)

Answer 6

Parallels arterial, plus superficial veins

Question 7

The shoulder is innervated by the brachial plexus.

What are the nerve roots of the brachial plexus?

Answer 7

C5-T1

Question 8

What are the 5 terminal nerves of the brachial plexus?

Are they sensory or motor?

Answer 8

Anterior cord:
Musculocutaneous, median, ulnar
Posterior cord:
Axillary, radial

MIXED - sensory and motor axons in the same nerve.

Question 9

What are the nerve roots of musculocutaneous nerve?
What is it’s motor function?
What is it’s sensory function?

Answer 9

C5-C7
Innervates muscles in anterior compartment of arm (coracobrachialis, biceps brachii and brachialis)
Innervates skin on the lateral surface of forearm (lateral cutaneous nerve of forearm).

Question 10

What are the nerve roots of median nerve?
What is it’s motor function?
What is it’s sensory function?
What sign is associated with its palsy?

Answer 10

C6 – T1
Innervates the flexor muscles in the anterior compartment of the forearm. Also innervates the thenar muscles and lateral two lumbricals in the hand.
Innervates lateral part of palm and lateral three and a half fingers on anterior surface of hand.
HAND OF BENEDICTION

Question 11

What are the nerve roots of ulnar nerve?
What is it’s motor function?
What is it’s sensory function?
What sign is associated with its palsy?

Answer 11

C8-T1
Innervates the muscles of the hand (apart from the thenar muscles and two lateral lumbricals), flexor carpi ulnaris and medial half of flexor digitorum profundus.
Innervates the anterior and posterior surfaces of the medial one and half fingers, and the associated palm area.
CLAW HAND

Question 12

What are the nerve roots of axillary nerve?
What is it’s motor function?
What is it’s sensory function?

Answer 12

C5 and C6
Innervates teres minor and deltoid.
Innervates the skin over the lower deltoid ‘(‘regimental badge area’).

Question 13

What are the nerve roots of radial nerve?
What is it’s motor function?
What is it’s sensory function?
What sign is associated with its palsy?

Answer 13

C5-T1
Innervates triceps brachii, and extensor muscles of forearm.
Innervates most of the skin of the posterior side of forearm, and the dorsal surface of the lateral side of the palm, and lateral three and a half digits.
WRIST DROP

Question 14

What are the two main pathologies of the shoulder?

Answer 14

Fractured clavicle and dislocated shoulder (glenohumeral joint).

Question 15

How might a clavicle fracture?
How many % of adult fractures does this account for?
When might it become a medical emergency?

Answer 15

Direct or indirect force
2-5%
If tingling or reduced peripheral pulses (blood supply and nerve supply compromised).

Question 16

How might the shoulder appear in a fractured clavicle?

Answer 16

Shoulder drooping
Rounded profile of shoulder (deltoid) maintained
Loss of width of shoulder

Question 17

How many % of population will suffer a dislocated shoulder? What is the recurrence rate?
Does it dislocate anteriorly or posterioly?

Answer 17

1.7%
50-89%
Anteriorly

Question 18

How will a shoulder appear in an anterior dislocation?

What nerve is at risk of injury and what will this result in?

Answer 18

Loss of rounded profile (due to deltoid stretched by arm being pulled down by gravity)
Acromion is more prominent
Axillary (deltoid paralysis)

Question 19

How will deltoid paralysis present? (5)

How can it be fixed?

Answer 19

Weakness in abduction of the arm
Can move arm when standing 
Leaning to side
Loss of roundness of the shoulder
Numbness over regimental badge

Nerve repair, or muscle transfer of pect major.

Question 20

Which nerve innervates deltoid?

What is the function of deltoid?

Answer 20

Axillary

Main abductor of arm

Question 21

Where is the lymphatic drainage of the shoulder (shared with drainage of lateral breast)?

Answer 21

Many lymph nodes in axilla, with nodes arranged in 5 groups.

Question 22

What are the five groups of axillary lymph nodes?

Answer 22

Humeral (lateral)
Central
Subscapular (posterior)
Apical
Pectoral (anterior)

Question 23

Where does upper limb lymph mainly drain into?

Answer 23

Humeral and central nodes

Question 24

Where does lymph of medial breast drain?

Answer 24

Parasternal nodes

Question 25

What muscles rotate the scapula? (2)

Answer 25

Trapezius and serratus anterior

Question 26

How many degrees does the scapula rotate the shoulder? What moves it the other 120 degrees?

Answer 26

60 | Glenohumeral joint

Question 27

What muscle does the first 10 degrees of abduction? | What muscle does the rest?

Answer 27

Supraspinatus | Deltoid

Question 28

What nerve innervates serratus anterior?

Answer 28

Long thoracic nerve

Question 29

Injury to long thoracic nerve causes...?

Answer 29

Winging of scapula

Question 30

What nerve innervates lat dorsi?

Answer 30

Thoracodorsal nerve

Question 31

When might long thoracic nerve or thoracodorsal nerve be injured?

Answer 31

Axillary lymph node clearance for metastatic breast cancer

Question 32

What nerve innervates trapezius?

Answer 32

Spinal accessory nerve

Question 33

In what condition is the winging more prominent – spinal accessory damage or serratus anterior palsy?

Answer 33

Serratus anterior palsy

Question 34

What might damage the spinal accessory nerve? (2)

Answer 34

Tumour around jugular foramen | Neck surgery

Question 35

How might spinal accessory palsy present?

Answer 35

Weak abduction (stop at about 70 degrees) Atrophy of trapezius Shoulder droops Scapula winging

Question 36

What are the bones of the arm?

Answer 36

Humerus

Question 37

What are the joints of the arm? (4) | What are for flexion and extension?* Which is for rotation?**

Answer 37

Glenohumeral | Elbow (humero-ulnar*, humero-radial* and proximal radio-ulnar**)

Question 38

What nerve and what artery run in the spiral groove in posterior compartment of arm?

Answer 38

Radial nerve | Deep artery of arm

Question 39

What nerves and artery are in the anterior compartment?

Answer 39

Median and musculocutaneous nerves | Brachial artery

Question 40

What nerve is at risk of injury with a midshaft humeral fracture?

Answer 40

Radial nerve

Question 41

What nerve is at risk of injury with a supracondylar fracture of the humerus?

Answer 41

Median nerve

Question 42

What nerve is at risk of injury in a medial epicondyle fracture?

Answer 42

Ulnar nerve

Question 43

What type of joint is the elbow?

Answer 43

``` Hinge joint (brings hand to body using humeroulnar and humeroradial) Pivot joint (turns hand over using proximal radio-ulnar) ```

Question 44

What are the bones of the forearm? (2)

Answer 44

Radius | Ulna (main stabilising bone)

Question 45

What are the joints of the forearm? (3)

Answer 45

Elbow, distal radioulnar joint and radiocarpal joint

Question 46

What muscles groups are in the anterior compartment of the forearm? What nerves? (2) What arteries? (2)

Answer 46

Flexors and pronators Median (main one) and ulnar nerves (for precision muscles) Radial and ulnar arteries

Question 47

What muscles groups are in the posterior compartment of the forearm? What nerve? What artery?

Answer 47

Extensors and supinators Radial nerve Posterior interosseus artery (comes off ulnar artery)

Question 48

What is the blood supply to the forearm? What are they terminal branches of and where do they start?

Answer 48

Ulnar and radial arteries Brachial artery Opposite neck of radius in inferior cubital fossa

Question 49

What are the bones of the hand? (3)

Answer 49

Carpals, metacarpals and phalanges

Question 50

What are the joints of the hand? (3)

Answer 50

Distal radioulnar, radiocarpal, intercarpals, carpometacarpals, metacarpalphalangeals and interphalangeals (distal and proximal)

Question 51

How many phalanges does the thumb have? What about the rest of the digits?

Answer 51

2 | 3

Question 52

What carpals does the radius articulate with? | What about the ulna?

Answer 52

Scaphoid and lunate | Does not articulate with carpals

Question 53

Where are the power muscles for the hand located?

Answer 53

In forearm (have long tendons that pass over wrist into hand)

Question 54

What is a common presenting sign of rheumatoid arthritis?

Answer 54

Carpal tunnel-like syndrome

Question 55

What is a Colles fracture? | What deformity does it result in?

Answer 55

Fracture of distal radius (within 2cm of distal end of radius). Dorsal displacement of distal fragment of radius results in dinner fork deformity.

Question 56

Fractures of distal radius and ulna make up what percentage of wrist injuries?

Answer 56

75%

Question 57

Why are there fewer injuries to carpals? | How many % of injuries to the hand does this account for?

Answer 57

Fewer injuries to carpals as there are ligaments to hold them in place. 10%

Question 58

In carpal tunnel syndrome, what nerve is compressed? What muscle group has atrophied? What protects the long flexor and extensor tendons from rubbing on the bones?

Answer 58

Median nerve Phenar muscle group Synovial tendon sheaths

Question 59

What are the compartments of the hand? (3)

Answer 59

Superficial - long flexor tendons and their sheaths Medial and lateral - hypothenar and thenar muscles Deep - intrinsic muscles of the hand

Question 60

How many % of population don't have collateral circulation in hand?

Answer 60

30%

Question 61

Radial and ulnar arteries anastomose in the...?

Answer 61

Superficial and deep palmar arches

Question 62

What 3 nerves from the brachial plexus terminate in the hand?

Answer 62

Median Radial Ulnar

Question 63

What % of hand movements does the thumb account for?

Answer 63

50%