Extrinsic Muscles of the Shoudler Flashcards Preview

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Flashcards in Extrinsic Muscles of the Shoudler Deck (46):
1

What are the muscles of the shoulder associated with?

Movements of the upper limb

2

What do the muscles of the shoulder produce?

The characteristic shape of the shoulder

3

What can the muscles of the shoulder be divided into?

Extrinsic 
Intrinsic

4

What are the extrinsic muscles of the shoulder?

Those that originate from the torso, and attach to the bones of the shoulder (clavicle, scapula or humerus)

5

What are the intrinsic muscles of the shoulder?

Those that originate form the scapula and/or clavicle, and attach to the humerus

6

Where are the extrinsic shoulder muscles located?

In the back

7

What are the extrinsic shoulder muscles organised into?

A superficial and deep layer

8

What are the superficial extrinsic shoulder muscles?

Trapezius 
Latissimus dorsi

9

What is the most superficial of all the back muscles?

The trapezius

10

What shape is the trapezius?

Broad, flat, triangular

11

What do the muscles on each side of the trapezius form?

A trapezoid shape

12

What is the proximal attachment of the trapezius?

Medial third of the superior nuchal line 
External occipital protuberance 
Nuchal ligament 
Spinous processes of C7-T12 vertebrae

13

What is the distal attachment of the trapezius?

Lateral third of clavicle 
Acromion 
Spine of scapula

14

What is the innervation of the trapezius?

Spinal accessory nerve (CN XI) 
C3, C4 spinal fibres

15

What is the function of the spinal accessory nerve on the trapezius?

Motor functions

16

What is the function of the C3 and C4 spinal nerves on the trapezius?

Pain reception and proprioception

17

What is the arterial supply of the trapezius?

Transverse cervical artery

18

What is the action of the trapezius?

Descending part elevates and rotates during abduction of arm
Ascending part depresses 
Middle part (or all parts together) retracts scapula 
Descending and ascending parts together rotate glenoid cavity superiorly

19

What is the most common cause of accessory nerve damage?

Iatrogenic

20

What is meant by iatrogenic?

Due to a medical procedure

21

What medical procedure in particular can cause trauma to the accessory nerve?

Operations such as cervical lymph node biopsy or cannulation of the internal jugular vein

22

How is the accessory nerve tested?

Trapezius function can be assessed

23

How can trapezius function be assessed?

By asking the patient to shrug his/her shoulders

24

What are the other clinical features of accessory nerve damage?

Muscle wasting
Partial paralysis of sternocleidomastoid 
Asymmetrical neckline

25

Where is the proximal attachment of the latissimus dorsi?

Spinous processes of the inferior 6 thoracic vertebrae (T6-T12) 
Thoracolumbar fascia 
Iliac crest 
Inferior 3 to 5 ribs

26

What happens to the fibres of the latissimus dorsi?

They converge into a tendon

27

What is the distal attachment of the latissimus dorsi?

Floor of intertubercular sulcus of humerus

28

What is the innervation of the latissimus dorsi?

Thoracodorsal nerve (C6-8)

29

What is the arterial supply of the latissimus dorsi?

Thoracodorsal artery

30

What is the action of the latissimus dorsi?

Extends, adducts, and medially rotates the humerus 
Raises body towards arm during climbing

31

What are the deep extrinsic muscles of the shoulder?

The levator scapulae 
Rhomboid minor 
Rhomboid major

32

Where are the deep extrinsic muscles of the shoulder?

In the upper back, under the trapezius

33

What shape is the levator scapulae?

Small, strap-like

34

What is the proximal attachment of the levator scapulae?

Posterior tubercles of the transverse processes of C1-C4 vertebrae

35

What is the distal attachment of the levator scapulae?

Medial border of the scapula superior to the root of the scapular spine

36

What is the innervation of the levator scapulae?

Dorsal scapular nerve (C4, C5)
Cervical nerve (C3, C4)

37

What is the arterial supply of the levator scapulae?

Transverse cervical artery and ascending cervical artery

38

What is the action of the levator scapulae?

Elevates scapula and rotates its glenoid cavity inferiorly by rotating scapula

39

Where is the rhomboid minor situated relative to the rhomboid major?

Superiorly

40

What is the proximal attachment of the rhomboid minor?

Nuchal ligament
Spinous processes of C7 and T1 vertebrae

41

What is the distal attachment of the rhomboid minor?

Smooth triangular area at medial end of scapular spine

42

What is the proximal attachment of the rhomboid major?

Spinous processes of T2-T5 vertebrae

43

What is the distal attachment of the rhomboid major?

Medial border of scapula from level of spine to inferior angle

44

What is the innervation of the rhomboid muscles?

Dorsal scapular nerve (C4, C5)

45

What is the action of the rhomboid muscles?

Retract scapula and rotate its glenoid cavity inferiorly
Fix scapula to thoracic wall

46

Draw a diagram illustrating the extrinsic muscle of the shoulder

Answer…