MSK 1 - Upper Limbs

Question 1

what is the axilla?

Answer 1

Is a pyramidal space below the shoulder joint. It provides a passageway for vessels and nerves going to and from the upper limb

Question 2

what is the shape of the axilla?

Answer 2

The axilla is roughly pyramidal in shape and has an apex, base, and 4 walls

Question 3

The anterior wall of axilla is formed by what?

Answer 3

Pectoralis major muscle and Pectoralis minor muscle

Question 4

The posterior wall of the axilla is formed by what 3 muscles?

Answer 4

subscapularis, Teres major and Latissimus dorsi

Question 5

Medial wall of the axilla is formed by what?

Answer 5

the thoracic wall and serratus anterior muscle

Question 6

Lateral wall of the axilla is formed by what?

Answer 6

the intertubercular groove of the humerus

Question 7

a

Answer 7

Brachial plexus

Question 8

b

Answer 8

Axillary lymph nodes (apical group on left and central group more lateral on the right)

Question 9

c

Answer 9

Axillary artery

Question 10

d

Answer 10

Axillary vein

Question 11

The axillary artery is the continuation of which artery?

Answer 11

Subclavian artery

Question 12

At what anatomical point does the axillary artery begin?

Answer 12

Outer boarder of the first rib

Question 13

The axillary artery continues beyond the axilla as which vessel?

Answer 13

Brachial artery

Question 14

At what anatomical point does the name of this vessel change

Answer 14

lower border of teres major

Question 15

CLinical:

The enlargement of ________________ is common in infection of the upper limb, and in malignant processes involving the breast tissue.

The ____________ is a point where vasculature can be _________ (via a tourniquet) in response to profuse bleeding to the upper limb – for example after tissue trauma

Answer 15

axillary lymph nodes

axillary artery

compressed

Question 16

_______________\_ is the major network of nerves innervating the upper limb. It begins in the cervical region and extends into axilla.

Answer 16

The Brachial Plexus

Question 17

what ofrms the brachial plexus?

Answer 17

Brachial plexus is formed by the ventral rami of

C 5 to T 1

Question 18

Which nerve roots form the upper trunk? (of brachial plexus?

Answer 18

C5 and C6

Question 19

Which roots of the plexus contribute to the lower trunk? (brachial plexus)

Answer 19

C8 and T1

Question 20

Which root forms the middle trunk? (brachial plexus)

Answer 20

C7

Question 21

The brachial plexus can be further sub divided into trunks, divisions, cords and terminal branches as it passes down into the arm

what is purple

Answer 21

roots

Question 22

The brachial plexus can be further sub divided into trunks, divisions, cords and terminal branches as it passes down into the arm

what is oragne

Answer 22

trunks

Question 23

The brachial plexus can be further sub divided into trunks, divisions, cords and terminal branches as it passes down into the arm

what is yellow

Answer 23

division

Question 24

The brachial plexus can be further sub divided into trunks, divisions, cords and terminal branches as it passes down into the arm

what is pink

Answer 24

cords

Question 25

The brachial plexus can be further sub divided into trunks, divisions, cords and terminal branches as it passes down into the arm

what is green

Answer 25

terminals

Question 26

The division of the trunks form three cords of the brachial plexus in the axilla. The cords are named for their position in relation to the ______________________

Answer 26

axillary artery in the axilla

Question 27

Clinical: Erb’s

Injury to upper trunk causes Erb’s Palsy, this results in a characteristic ‘waiter’s tip’ appearance of the upper limb - medial rotation of the arm with wrist flexion. This is caused by a hyper-extension injury of the head from the shoulder

Which group of muscles are affected in this condition? They are supplied by the nerve roots C5 -C6 (you should answer this question after studying the relevant regions)

Answer 27

rotator cuff muscles

Question 28

Clinical: Klumpke’s Palsy

Injury to the lower trunk causes Klumpke’s Palsy

what does this affect

Answer 28

This mainly affects the intrinsic muscles of the hand (typically a claw hand), flexors muscles of the wrist and flexor muscles of the fingers (you will study these muscles later)

Both injuries are most commonly caused by shoulder dystocia at birth or following traumatic injury (e.g. motor vehicle accident)

Question 29

1. _______ nerve from the posterior cord
2. ______ nerve from the posterior cord
3. ______________ nerve from the lateral cord
4. _____ nerve from the medial cord
5. ______ nerve from both the lateral and medial cord

Answer 29

Axillary

Radial

Musculocutaneous

Ulnar

Median

https://geekymedics.com/brachial-plexus/

Question 30

a

Answer 30

Subclavian artery

Question 31

b

Answer 31

Axillary artery

Question 32

c

Answer 32

Brachial artery

Question 33

d

Answer 33

Ulnar artery

Question 34

e

Answer 34

Radial artery

Question 35

a

Answer 35

Cephalic vein

Question 36

b

Answer 36

Basilic vein

Question 37

c

Answer 37

Median cubital vein

Question 38

Clinical:

Throughout your medical career you will become very accustomed to finding the superficial veins of the upper arm. They are the most common place for ___________ (taking blood) and _________ (allowing for intra-venous medications and blood transfusions to be delivered)

Answer 38

venepuncture

cannulation

Question 39

The _______________ is a complex network of veins lying at the distal aspect of the upper limb

All the superficial veins of the upper limb lie in the _______________, just underneath the skin making them easy to access for various procedures

Answer 39

dorsal venous arch

subcutaneous tissue

Question 40

The _________ vein arises at the lateral end of the dorsal venous arch and _______ vein arises at the medial end of the dorsal venous arch

Answer 40

Cephalic

Basilic

Question 41

Median cubital vein is a large communicating vein which shunts blood from the ________ vein to the ________ vein

Often the median cubital vein is in a fixed position in the ante-cubital fossa – this is handy as it is the most common site for venepuncture

Answer 41

cephalic

basilic

Question 42

The ________ vein ascends the arm on its lateral aspect, piercing the clavipectoral fascia draining into the axillary vein

The _______ vein ascends on the medial side of the arm, passing deep at the mid-humeral level and eventually becoming the axillary vein at the lower border of teres minor

Answer 42

cephalic

basilic

Question 43

________ is more superficial compared to the ______ vein, blood drains deeper

Answer 43

Cephalic

basilic

Question 44

The area of skin supplied by one spinal segment is called a __________

Answer 44

dermatome

Question 45

In the upper limb each brachial plexus root (C5 to T1) can be mapped to a specific dermatome

where about are they?

(anterior)

Answer 45

(posteiror)

Question 46

Clinical:

Following an injury to a ___________ a sensory loss (paraesthesia) will be mapped on the skin corresponding to that specific __________.

Injury to a terminal branch produces sensory loss corresponding to the area of ____________________. This will become clearer through the workbook!

Remember these dermatomes as you require this knowledge to detect peripheral nerve injuries

Answer 46

spinal root

dermatome

distribution of that nerve

Question 47

Some simple embryology will help to explain their organisation: imagine the limb abducted to 90 degrees, resembling the arrangement in the embryo. The dermatomes are then roughly arranged from upper to lower; C5-T1.
As the limb bud expands the middle levels become squeezed out towards the tip of the limb, to form the adult pattern

Answer 47

Early stages of development in left photo

Later stages of development in right photo

Question 48

All lymphatic vessels from the upper limb drain into ___________ (lymph nodes are difficult to see in the dissected cadaver)

Answer 48

axillary nodes

Question 49

Axillary lymph nodes are divided into 4-5 distinct groups, what are they?

Answer 49

1. Anterior or pectoral group
2. Posterior or subscapular group
3. Apical group
4. Central group
5. Lateral or brachial group

Question 50

Which group of lymph nodes will be involved if the lymphatic spread of infection/cancer begins in the following areas of the body?

Choose your answer to the below from the following lymph node groups

• *1) Axillary
  2) Internal thoracic (internal mammary)
  3) Superficial Inguinal**

1. Infection of the little finger
2. Boil in the scapular region
3. Medial part of the breast (close to sternum)
4. Lateral part of breast (close to axilla)
5. Infection around the umbilicus: This infection can spread to both axillary and superficial inguinal groups of both sides? Why?

Answer 50

a = 1

b = 1

c = 2

d = 1

e = Equidistance between the nodes so top half goes up and bottom half down, due to the amount of blood vessels and lymph around the umbilicus

Question 51

Clinical:
___________ of the ________ nodes is frequent in malignant disease and infective processes affecting the upper back and shoulder, the front of the chest and mammary gland, upper anterolateral abdominal wall and upper limb

Answer 51

Enlargement

axillary

Question 52

The pectoral girdle or (shoulder girdle) is the set of bones which connects the upper limb to the axial skeleton on each side

what makes it up?

Answer 52

Question 53

what is the structure of the clavicle

Answer 53

To attempt to orientate and ‘side’ a clavicle there are a number of features which can help do so

1. The lateral aspect of a clavicle is flatter than the medial aspect
2. The superior surface is smoother than the inferior surface
3. The conoid tubercle – attachment for the conoid ligament – is on the inferior aspect of the lateral portion of the clavicle

Question 54

diagram which part of the clavicle is weakest and commonly breaks (fractures) during a fall. Why is this?

Answer 54

Middle third of the clavicle is the thinnest and most outermost part and has a lack of support by muscles and ligaments, so its more vulnerable to injury

Junction between middle and lateral thirds of the clavicle due to the weight of the arm

Question 55

a

Answer 55

Supraspinous fossa

Question 56

b

Answer 56

Spine of the scapula

Question 57

c

Answer 57

Infraspinous fossa

Question 58

d

Answer 58

Superior angle

Question 59

e

Answer 59

Medial border

Question 60

f

Answer 60

Subscapular fossa

Question 61

g

Answer 61

Lateral border

Question 62

h

Answer 62

Inferior angle

Question 63

i

Answer 63

Acromion

Question 64

j

Answer 64

Coracoid process

Question 65

k

Answer 65

Supraglenoid tubercle

Question 66

l

Answer 66

Glenoid cavity

Question 67

m

Answer 67

Infra-glenoid tubercle

Question 68

What type of synovial joint are the acromioclavicular (AC) and sternoclavicular (SC) joints?

Answer 68

AC joint - Synovial plane

SC joint - Synovial saddle

Question 69

Clinical:
Movement of the pectoral girdle involves _____________ joints, all moving simultaneously. Functional defects of any one of these joints impair movements of the pectoral girdle. Mobility of the _______ is essential for the freedom of movement of upper limb.

Answer 69

SC, AC and shoulder

scapula

Question 70

Abduction of the arm occurs in 2 stages: what are they?

Answer 70

The first 30 degrees of abduction is caused by muscles acting at the shoulder joint (gleno-humeral joint).
Beyond 30 degrees, abduction relies on the scapula being pulled upwards (elevated) and laterally rotating on the chest wall (“scapula-thoracic” movement)

This is called the scapulo-humeral rhythm

For every 3 degrees of abduction past the initial 30 degrees – 2 degrees occurs at the gleno-humeral joint, and 1 degree occurs due to “scapula-thoracic” movement (2:1 ratio)

Question 71

Review the movements of the scapula and therefore the pectoral girdle described below. These are essential in clinical testing of muscle function.

Scapular movement = elevation

what are the main muscles involved?

Answer 71

upper trapezius

levator scapulae

Question 72

Scapular movement = depression

what are the main muscles involved?

Answer 72

lower trapezius

Question 73

Scapular movement = Protraction (forward movement)

what are the main muscles involved?

Answer 73

serratus anterior

Question 74

Scapular movement = Retraction (backward movement)

what are the main muscles involved?

Answer 74

Trapezius (middle fibres) and Rhomboids

Question 75

Scapular movement = Lateral (upward) rotation: Elevating Glenoid Cavity - Shrugging your shoulders!

what are the main muscles involved?

Answer 75

upper and middle trapezius ??

Question 76

Scapular movement = Medial (downward) rotation: Depressing Glenoid Cavity

what are the main muscles involved?

Answer 76

1. Gravity
2. Levator scapulae
3. Rhomboid Maj. and Min.
4. Pectoralis minor

Question 77

1

Answer 77

Trapezius

Question 78

2

Answer 78

Levator scapulae

Question 79

3

Answer 79

Rhomboideus minor

Question 80

4

Answer 80

Rhomboideus major

Question 81

5

Answer 81

Supraspinatus

Question 82

6

Answer 82

Infraspinatus

Question 83

7

Answer 83

Teres minor

Question 84

8

Answer 84

Teres major

Question 85

9

Answer 85

Latissimus dorsi

Question 86

The shoulder joint is a synovial ball and socket joint, where the ball is the head of the ________ and socket is the _______ cavity. The rim of cartilage surrounding the socket is the glenoid _______

Answer 86

humerus

glenoid

labrum

Question 87

What is the function of this cartilage? (glenoid labrum)

Answer 87

Deepens the cavity, increases surface area of shoulder joint

Question 88

whata re the ligaments like of the shoudler joint?

Answer 88

The joint capsule of the glenohumeral joint is thickened to form definable ligaments, but true ligaments are also present between other bony elements. Together these strengthen and ease movements at the joint

Question 89

a

Answer 89

The Coracoacromial ligament

Question 90

b

Answer 90

Coracohumeral ligament

Question 91

c

Answer 91

Glenohumeral ligaments – strengthen the anterior aspect of the joint capsule

Question 92

d

Answer 92

The transverse humeral ligament – forms the roof of the bicipital groove

Question 93

The coracohumeral ligament strengthens _______ aspect of the joint capsule

Answer 93

superior

Question 94

The coraco-acromial arch is made up of the _______ and ________ process of scapula and ___________ ligament

It prevents __________ displacement of the humeral head

Answer 94

acromion

coracoid

Question 95

Which part of the shoulder joint capsule is weakest, as it is not protected by muscles or ligaments?

Answer 95

inferior

Question 96

Bursae Around the Shoulder Joint:

what is their function

Answer 96

Bursae are important as they provide cushioning around joints via. their synovial fluid filled interior – they essentially act as shock absorbers!

Question 97

The 2 main bursa in the shoulder are what?

Answer 97

The 2 main bursa in the shoulder are the subacromial(subdeltoid)bursa and subscapular bursa

Question 98

where is the subacromial bursa located?

Answer 98

Notice how the subacromial bursa sits between the infra-/supra-spinatus muscles and the deltoid, extending superiorly to lie below the acromion and coracoacromial ligaments

Question 99

Which bursa communicates with the joint cavity?

Answer 99

Subscapular bursa

Question 100

What is the role of subacromial bursa?

Answer 100

Sevres as a gliding mechanism between the rotator cuff and coracoacromial arch. Reduce friction in the space under the acromion

Question 101

What common sporting injury damages the subacromial bursa?

Answer 101

Subacromial bursitis, torn rotator cuff

Question 102

what muscle is shown, what is its proximal and sital attachment and what movement does it cause at the shoulder joint?

Answer 102

subscapularis

Medial 2/3 of costal aspect of scapula

Lesser tuberosity, shoulder joint capsule, and the front of the upper shaft of the humerus

Adductor and medial rotator of the humerus

Question 103

what muscle is shown, what is its proximal and sital attachment and what movement does it cause at the shoulder joint?

Answer 103

supraspinatus

Supraspinous fossa of the scapula and from fascia overlying the muscle

Greater tuberosity of humerus

abduction

Question 104

what muscle is shown, what is its proximal and sital attachment and what movement does it cause at the shoulder joint?

Answer 104

infraspinatus

Infraspinous fossa of scapula

Middle facet of the greater tuberosity of the humerus

Lateral rotator of the humerus

Question 105

what muscle is shown, what is its proximal and sital attachment and what movement does it cause at the shoulder joint?

Answer 105

teres minor

Upper two thirds of the lateral border of the scapula

Lesser tuberosity of humerus

Adductor and lateral rotator of the humerus

Question 106

Although the rotator cuff muscles have a role in movement at the glenohumeral joint, what is their primary function?

Answer 106

Stabilise the glenohumeral joint by compressing the humeral head against the glenoid

Question 107

Clinical:
Rotator cuff injuries are an important (and a potentially career-ending) cause of sport injury. These are caused by what?

Answer 107

repetitive overhead motions, e.g. serving in tennis; or throwing motions, e.g. pitching a baseball. Over time the increased stress on the ligaments and muscles weakens them, making them more likely to tear.

Question 108

The deltoidmuscle has a long origin spanning ___ bones

Answer 108

two

Question 109

what is the origin and insertion of the dletoid muscle?

Answer 109

It arises from the lateral spine of the scapula, passing across the acromion to the lateral third of the clavicle. Its distal attachment is to the deltoid tuberosity of the humerus

Due to its extensive proximal origin, different parts of the muscle will move the humerus in different directions.

Question 110

what is the function of the deltoid

Answer 110

Anterior fibres of deltoid flex and internally rotates at the shoulder joint

Middle fibres abductor the arm at the shoulder joint

Posterior fibres extend and laterally rotates at the shoulder joint

Question 111

What is the nerve supply to deltoid?

Answer 111

Axillary nerve

Question 112

In what common injury is this nerve often trapped and therefore damaged? (axillary nerve)

Answer 112

Shoulder dislocation (also occurs in fracture of the surgical neck of the humerus as wraps around here)

Question 113

As this is a mixed nerve, where would you test for loss of sensation to determine if a nerve injury had occurred? (axillary nerve)

Answer 113

C5 and 6, lateral arm, forearm, thumb and index finger

Abducted against resistance at approx. 15 degrees - motor

Question 114

what is the proximal and distal attachement of the pectoralis major?

Answer 114

The pectoralis major muscle has an extensive origin from the medial third of the clavicle, sternum and costal cartilage of the first 6 ribs and rectus sheath!

The distal attachment of this muscle is to the lateral lip of the bicipital groove of the humerus

Question 115

what is the action of the pectoralis major?

Answer 115

Its action on the shoulder joint is to adductor the shoulder and internal/medial rotate the humerus at the glenohumeral joint

Pectoralisminor lies deep to the pectoralis major muscle and is important anatomically as it splits the axillary artery into 3 parts. Along with serratusanterior it serves to stabilise the scapula during limb movements by keeping it pulled against the thoracic cage

The latter has an important role in protraction of the scapula

Question 116

Clinical Case – A Post-Operative Problem…

Mrs Smith is 64 years old and had a left mastectomy with axillary lymph node clearance for breast cancer.
Oddly she’s recently found that she can feel her scapula protruding outwards from her back when she’s been showering, and she is struggling to lift items on her left side.

Why has this occurred, which nerve has been damaged in the procedure?

Answer 116

Long thoracic nerve is vulnerable in breast surgery

Supplies the serratus anterior

Question 117

1

Answer 117

Trapezius

Question 118

2

Answer 118

Latissimus dorsi

Question 119

3

Answer 119

Teres major

Question 120

4

Answer 120

Deltoid

Question 121

Trapezius has a long origin meaning that its fibres approach the spine of the scapulae from above, in-line and below it. This results in different movements upon contraction of different parts of the muscle

Superior fibres of trapezius ______ the scapula

Middle fibres of trapezius ______ the scapula (move it back on the thorax)

Inferior fibres of trapezius ________ the scapula

Answer 121

elevate

retracts

depress

Question 122

Trapezius has an unusual innervation from a cranial nerve – which one?

Which foramen of the skull does this nerve pass through?

Answer 122

Accessory nerve

Jugular foramen

Question 123

Clinical:

‘Shrugging’ or elevation of the ________ is therefore one of the tests for cranial nerve function

Answer 123

shoulders

Question 124

shoulder joint movement = Flexion of shoulder (sagittal plane)

what are the shoulder joint muscles causing this?

Answer 124

1. anterior fibres of the deltoid
2. pectoralis major
3. coracobrachialis
4. long head of the biceps brachii

Question 125

shoulder joint movement = Extension of shoulder (sagittal plane)

what are the shoulder joint muscles causing this?

Answer 125

1. latissimus dorsi
2. teres major
3. pectoralis major ?????
4. posterior fibres of deltoid
5. Long head of triceps brachii

Question 126

shoulder joint movement = Adduction of shoulder joint

what are the shoulder joint muscles causing this?

Answer 126

1. coracobrachialis
2. pectoralis major
3. latissimus dorsi
4. teres major
5. subscapularis

Question 127

shoulder joint movement = Abduction of shoulder joint

what are the shoulder joint muscles causing this?

Answer 127

0 to 90 degrees:

1. supraspinatus
2. middle fibres of the deltoid

90 to 180 degrees:

1. serratus anterior
2. trapezius

Question 128

shoulder joint movement = Medial or internal rotation

what are the shoulder joint muscles causing this?

Answer 128

1. Subscapularis
2. Latissimus dorsi
3. Pectoralis major
4. Teres major
5. anterior fibres of the deltoid

Question 129

shoulder joint movement = Lateral or external rotation

what are the shoulder joint muscles causing this?

Answer 129

1. posterior fibres of the deltoid
2. teres minor
3. infraspinatus