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Flashcards in 3 - Muscles of Back Deck (51):
1

What is the muscle found in the picture?

The trapezius

2

What nerve provides motor innervation of the trapezius?

The accessory nerve

3

What are the roots of the accessory nerve?

C1 - C6

4

What are the roots of the accessory nerve specific to sensory function?

C3 and C4

5

What are the actions of the trapezius?

The upper fibres of the trapezius elevate the scapula and rotate it during abduction of the arm. The middle fibres retract the scapula and the lower fibres pull the scapula inferiorly

6

How would you test the accessory nerve?

test how well the trapezius is functioning. You can do this by getting the patient to elevate the shoulder against resistance.

7

What is the muscle shown in the picture?

Latissimus dorsi

8

What innervates latissimus dorsi?

Thoracodorsal nerve

9

What actions is the latissimus dorsi responsible for?

Extension of the arm at the shoulder, adduction at the shoulder and medial rotation of the arm

10

What is the muscle in the picture?

Levator Scapulae

11

What does Levator Scapulae attach?

Medial border of the scapulae

12

Where does latissimus Dorsi attach?

attaches to the intertubecular sulcus of the humerus

13

Where does trapezius attach?

All fibres attach to the posterior surface of the scapula and the clavicle.

14

What innervates levator scapulae?

Dorsal Scapula nevere

15

What are the actions of the levator scapulae?

Elevates scapula. Rotates scapula to tilt glenohumeral joint inferiorly

16

What are the muscles shown in the picture?

The Rhomboids major and minor

17

Where do the rhomboids attach?

The medial border of the scapula

18

What are the rhomboids innervated by?

Dorsal scapula nerve

19

What are the actions of the rhomboids?

Retracts scapula. Rotates scapula to tilt glenohumeral joint inferiorly. Can also fix the scapula to the thoracic wall.

20

What is the muscle shown in the picture?

Deltoid

21

What three sections are the deltoids divided into?

Anterior, middle and posterior

22

What does the deltoid attach to?

The deltoid tuberosity on the l;ateral surface of the humerus

23

What are the deltoids innervated by?

The axillary nerve

24

PWhat is the function of the anterior fibres of the deltoids?

The anterior fibres flex the arm at the shoulder, the posterior fibres extend the arm at the shoulder

25

What is the function of the middle fibers of the deltoid?

The middle fibres are the major abductor of the arm – it takes over from the supraspinatus, which abducts the first 15 degrees.

26

What is the muscle shown in the picture?

Teres major

27

What does teres major form?

The inferior border of the quadrangular space

28

What does teres major attach?

Intertubecular groove of humerus

29

What is the innervation of teres major?

Lower subscapular nerve

30

What are the actions of teres major?

Adducts at the shoulder and medially rotates the arm

31

What are the rotator cuff muscles?

A group of 4 muscles that originate from the scapula and attach to the humeral head, pulling it into the glenoid fossa.

32

What do rotator cuff muscles provide?

Stability to the glenohumeral joint

33

What is A?

Supraspinatus

34

What is the origin and attachment of the supraspinatus?

Originates from the supraspinous fossa on the posterior surface of the scapula, attaches to the greater tuberosity of the humerus

35

What is the innervation of the supraspinatus?

Suprascapular nerve

36

What are the actions of the supraspinatus?

Responsible for first 15 degrees of abduction, assists deltoid for the rest.

37

What is B?

Infraspinatus

38

What is the origin and attachments of the infraspinatus?

Originates from the infraspinous fossa, attaches to the greater tubercle of the humerus

39

What is the innervation of the infraspinatus?

Suprascapular nerve

40

What are the actions of the infraspinatus?

Lateral rotation of arm

41

What is C?

Teres minor

42

What are the origins and attachments of teres minor?

Originates from midway down the medial border, attaches to the greater tubercle of the humeru

43

What is the innervation of teres minor?

Axillary nerve

44

What is the action of teres minor?

Lateral rotation of the arm

45

What is D?

Subscapularis

46

What are the origins and attachments of the subscapularis?

Originates from the subscapular fossa, on the costal surface of the scapula. It attaches to the lesser tubercle of the humerus

47

What is the innervation of the subscapularis?

Upper and lower subscapular nerves

48

What is the action of the subscapularis?

Actions: Medially rotates arm

49

What is painful arc?

pain in the middle of abduction, where the affected area comes into contact with the acromion

50

What causes painful arc?

When the arm is abducted, the tendon of the supraspinatus muscle ‘rubs’ against the coraco-acromial arch. The friction is reduced by the subacromial bursa.Under repetitive use, there are degenerative changes in both the subacromial bursa and the supraspinatus tendon.

51

What causes rotator cuff tendonitis?

Repetitive use of the rotator cuff muscles can cause the head of the humerus and the muscles to irritate the coraco-acromial arch, which in turn causes inflammation of the rotator cuff