MSK - Upper Limb

Question 1

Define “the axilla”, and identify the muscles that form its anterior and posterior walls.

Answer 1

Axilla is pyramidal space inferior to the shoulder joint and just superior to the hollow that patient’s will refer to as the “armpit”

Anterior: Pectoralis major

Posterior: Teres major

Question 2

Name the major vessels and nerves that pass through axilla

Answer 2

Axillary artery

Axillary vein - continuation of brachial vein (deep vein of arm), becomes axillary vein at lower border of teres major

Components of brachial plexus

Question 3

What is the arrangement of the apical axillary adipose tissue lymph nodes?

Answer 3

Superiorly - drain towards the right lymphatic duct/thoracic duct

Question 4

What is the arrangement of the central axillary adipose tissue lymph nodes?

Answer 4

Drain to apical nodes

Question 5

What is the arrangement of the basal axillary adipose tissue lymph nodes?

Answer 5

Drain to central nodes
- Pectoral - along lateral border of pec minor and receive much lymph from the breast

• Subscapular - receive lymph from scapular region
• Humeral - receive most of upper limb lymph

Question 6

What is the brachial plexus?

Answer 6

The brachial plexus supplies the upper limb and is formed from a very specific intertwining of the anterior rami of spinal nerves C5 – T1

Question 7

From proximal to distal, the brachial plexus consists of?

Answer 7

Roots - Trunks - Divisions - Cords - Names Nerves

Question 8

What are the roots of the brachial plexus?

Answer 8

What are the roots of the brachial plexus?

Question 9

What are the trunks of the brachial plexus?

Answer 9

Combinations of roots, which give rise to divisions.

• Superior = combined anterior rami of C5 & C6 spinal nerves
• Middle = anterior ramus of C7 spinal nerve
• Inferior = combined anterior rami of C8 & T1 spinal nerves

Question 10

What are the divisions of the brachial plexus?

Answer 10

What are the trunks of the brachial plexus?

Question 11

What are the cords of the brachial plexus?

Answer 11

The cords are named according to their relationship to axillary artery.

• Medial = a direct continuation of the anterior division of the inferior trunk
• Lateral = formed from the anterior divisions of the superior and middle trunks
• Posterior = formed from the posterior divisions of all three trunks

Question 12

What are the named nerves of the brachial plexus?

Answer 12

The cords combine to give the named nerves of the brachial plexus.

• The ulnar nerve continues directly from the medial cord
• The musculocutaneous nerve continues directly from the lateral cord
• The posterior cord divides into the axillary nerve and radial nerve
• The medial and lateral cords both contribute the formation of the median nerve

Question 13

Where are the roots and trunks of the brachial plexus?

Answer 13

Lie mainly between the anterior and middle scalene muscles in the root of the neck.

Question 14

Where are the divisions of the brachial plexus?

Answer 14

Immediately posterior to the subclavian vessels in the root of the neck (deep to the clavicle)

Question 15

Where are the cords of the brachial plexus?

Answer 15

Around the axillary artery, which is distal to 1st rib

Question 16

Which muscles does the musculocutaneous nerve supply?

Answer 16

Coracobracialis, biceps brachii, brachialis

Question 17

Where to the axillary nerves and radial nerves eventually pass into?

Answer 17

Posterior compartment of arm

Question 18

What is the course of the axillary nerve?

Answer 18

Lies superior to radial nerve, wraps around posterior aspect of surgical neck of humerus

Question 19

What injury can damage the axillary nerve?

Answer 19

Shoulder dislocation/fractured neck of humerus

Question 20

What structure does the radial nerve wrap around?

Answer 20

Posterior aspect of mid-shat of humerus (may be injured by mid-shaft humeral fracture)

Question 21

The ulnar nerve is the most medial/lateral of the named nerves of the brachial plexus

Answer 21

MEDIAL

Question 22

The ulnar nerves passes anteriorly/posteriorly into medial/lateral aspect of arm

Answer 22

POSTERIORLY

MEDIAL

Question 23

What part of the ‘M-shaped” configuration of the named nerves within the axilla does the median nerve form?

Answer 23

Middle

Question 24

What are the bones of the pectoral (shoulder) girdle?

Answer 24

Scapula, clavicle, manubrium of sternum

Question 25

By what 3 joints does the pectoral girdle permit articulation of upper limb with appendicular skeleton?

Answer 25

Glenohumeral, acromioclavicular, sternoclavicular Offer increased range of movement for hand function

Question 26

What is the role of the pectoral girdle?

Answer 26

Maintain relatively lateral position of upper limb

Question 27

How is the pectoral girdle stabilised?

Answer 27

By providing attachment points for ligaments and muscles

Question 28

What role does the posterior (spinal) part of the deltoid play in shoulder movement?

Answer 28

Extension at shoulder

Question 29

What role does the middle (acromial) part of the deltoid play in shoulder movement?

Answer 29

ABduction at shoulder (taking over from spuraspinatus beyond 15 degrees)

Question 30

What role does the anterior (clavicular) part of the deltoid play in shoulder movement?

Answer 30

Mainly flexion at shoulder

Question 31

What role does the ascending trapezius play in shoulder movement?

Answer 31

Scapular depression

Question 32

What role does the middle trapezius play in shoulder movement?

Answer 32

Scapular retraction

Question 33

What role does the descending trapezius play in shoulder movement?

Answer 33

Scapular elevation

Question 34

What movement do the ascending and descending parts of the deltoid co-ordinate to produce?

Answer 34

Superior rotation of glenoid fossa

Question 35

What movements does the Levator scapulae produce?

Answer 35

Elevation of scapula and inferior rotation of glenoid fossa

Question 36

What movements do the Rhomboids produce?

Answer 36

Major - retraction of scapula and inferior rotation of glenoid fossa Minor - retraction of scapula and inferior rotation of glenoid fossa

Question 37

What muscles make up the rotator cuff?

Answer 37

``` SITS Supraspinatus Infraspinatus Teres minor Subscapularis ```

Question 38

What does the supraspinatus do?

Answer 38

First 15 degrees of abduction at shoulder

Question 39

What do the teres minor/ infraspinatus do?

Answer 39

Stabilise head of humerus in glenoid/lateral rotation at shoulder

Question 40

What does the subscapularis do?

Answer 40

Stabilise head of humerus in glenoid/medial rotation at shoulder

Question 41

What does the teres major do?

Answer 41

ADduction/medial rotation at shoulder

Question 42

What are the non-rotator cuff muscles that attach to the pectoral girdle?

Answer 42

Teres major, pectoralis major, pectoralis minor and serratus anterior

Question 43

Why must the scapula rotate to allow for full adduction/abduction of the upper limb to occur?

Answer 43

So that the glenoid fossa faces more inferiorly/superiorly respectively. Superior rotation of the glenoid is required to prevent the greater tubercle of the humerus from impinging on the acromion of the scapula i.e. without superior rotation of the scapula we would be unable to fully abduct our upper limb.

Question 44

What is the distal insertion of the supraspinatus/infraspinatus/teres minor?

Answer 44

Greater tubercle of humerus

Question 45

What is the distal insertion of the subscapularis?

Answer 45

Lesser tubercle of humerus

Question 46

What is the innervation of the rotator cuff muscles?

Answer 46

Branches of brachial plexus

Question 47

What is "painful arc syndrome"?

Answer 47

Impingement of supraspinatus tendon between the humerus and the acromion process can lead to “painful arc syndrome”; patients with this condition typically complain of pain during 50-130° of abduction.

Question 48

What will a patient with supraspinatus paralysis/tendon tear do to initiate ABduction?

Answer 48

Throw upper limbs to the side

Question 49

What function to the distal tendon attachments of the rotator cuff muscles serve in the shoulder joint?

Answer 49

Strengthens it

Question 50

What is the most common rotator cuff injury?

Answer 50

Partial tear or complete rupture of supraspinatus tendon

Question 51

Understand the glenohumoral joint | State the type of joint

Answer 51

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Question 52

Understand the glenohumoral joint | Describe the key osteology

Answer 52

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Question 53

Understand the glenohumoral joint Identify the principle ligaments (coraco-clavicular, coraco-acromial, coraco-humeral & glenohumeral) and how they affect stability

Answer 53

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Question 54

Understand the glenohumoral joint | Know the location of the subacromial bursa and its relationship to the supraspinatus tendon

Answer 54

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Question 55

Understand the glenohumoral joint Identify the glenoid labrum and anatomical neck of the humerus, and know they represent the attachments of the joint capsule

Answer 55

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Question 56

Understand the glenohumoral joint Understand why dislocation of the shoulder joint is common and may be associated with axillary nerve injury. Know how to test axillary nerve motor and sensory function.

Answer 56

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Question 57

Understand the elbow joint | Describe the bony anatomy of the elbow and radioulnar joints and the ligaments mentioned in this manual.

Answer 57

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Question 58

Understand the elbow joint Be aware that the elbow joint can dislocate and that the head of the radius can dislocate from within the annular ligament. Know that this is common in children.

Answer 58

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