Anterior and Posterior Thorax Muscle Flashcards Preview

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Flashcards in Anterior and Posterior Thorax Muscle Deck (52):
1

Muscles can be named after these three things

Action, Shape, Location (origin and insertion)

2

These muscles attach the upper limb to the axial skeleton via the pectoral girdle

Muscles of the anterior and posterior thorax

3

These muscle stabilize the shoulder and move the scapula

Muscles of the anterior and posterior thorax

4

Name the 6 muscles of the anterior thorax

1. Pectoralis Minor
2. Serratus Anterior
3. Subclavius
4. Sternocleidomastoid
5. Anterior Scalene
6. Pectoralis Major

5

A triangular shaped muscle with the apex attached to the coracoid process, distally attached to ribs 3-5

Pectoralis Minor

6

Located on the anterior wall of thorax and is covered by pectoralis major muscle

Pectoralis Minor

7

Innervation of the pectoralis minor

medial pectoral nerve

8

Stabilizes the scapula through the coracoid process, and can sometimes lift the ribs up

Pectoralis Minor

9

Muscle with scalloped origin, serratis saw, sometimes called the boxers muscle

Serratus Anterior

10

Holds the scapula against the chest wall and is important to protract the scapula

Serratus Anterior

11

Needed to elevate the arm above 90 degrees by rotating laterally, paralysis would inhibit raising arm above 90 degrees

Serratus Anterior

12

Origin and insertion of serratus anterior

Origin: Lateral aspects of ribs 1-8

Insertion: Posteriorly to vertebral border of scapula

13

Innervatation of the serratus anterior

the long thoracic nerve

14

Small muscle lying below the clavicle and holds the clavicle in the sternoclavicular joint

Subclavius

15

Protects the underlying subclavian vessels if there is a fracture of the clavicle, which could pierce the subclavian artery which supplies the upper extremity

Subclavius

16

Origin and insertion of the subclavius

Origin: Costal cartilage of rib one

Insertion: Inferior surface of the lateral third of the clavicle

17

Innervation of the clavicle is the nerve to the ___ which is a branch of the brachioplexus

Subclavius

18

Action is to stabilize the pectoral girdle and help to depress the shoulder

Subclavius

19

The anterior neck muscle with two heads, one clavicular and the other sternal

Sternocleidomastoid

20

Attaches pectoral girdle to the axial skeleton and bilaterally flexes head foward

Sternocleidomastoid

21

Unilaterally flexes head to the same side

Sternocleidomastoid

22

The sternocleidomastoid is innervated by

the spinal accessory nerve (cranial nerve 11)

23

Bilaterally contracted causes head to move forward

Sternocleidomastoid

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Group of three muscles located beneath the sternocleidomastoid

Scalene (Anterior, Middle, and Posterior)

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Lies directly deep to sternocleidomastoid muscle

Anterior Scalene

26

Origin and insertion of anterior scalene

Origin: Cervical Transverse Processes 3/4-6

Insertion: Rib one

27

Innervation of the anterior scalene

Branches of cervical spinal nerves

28

If contracted, it depends on which part is fixed

Neck is fixed -> ribs will elevate as in deep inspiration

If rib is fixed -> neck flexes forward, especially when contracting bilaterally

One side is contracted -> lateral flexion to same side

Anterior Scalene

29

A very large artery runs posterior to the anterior scalene

Subclavian Artery

30

Covers the sternocleidomastoid and is considered a muscle of facial expression

Platysma

31

The five muscles on the posterior thorax

Trapezius
Levator Scapulae
Rhomboid Major
Rhomboid Minor
Latissimus Dorsi

32

Muscle on posterior thorax that attaches the pectoral girdle to the trunk, has a trapezoid shape, and its fibers divide into three actions

Trapezius

33

Three actions of the trapezius

Elevates Scapula
Retracts Scapula
Depresses Scapula

34

This muscle also braces the shoulders by pulling the scapulae posteriorly and superiorly, fixing them in position on the thoracic wall with tonic contraction

Therefore, weakness of the muscle causes droopy shoulders

Trapezius

35

Originates from the occipital bone from the ligamentum nucae

Trapezius

36

A very thick ligament attached to the spinous processes of the upper cervical vertabrae

ligamentum nucae

37

Attaches to spinous cervical 7-12 thoracic vertebrae

Trapezius

38

Laterally attaches to clavicle, acromion process of scapula , and spine of scapula

Trapezius

39

Innervated of the trapezius

Spinal Accessory Nerve (cranial nerve 11)

40

Upper fibers of trapezius do this to the scapula

Middle fibers do this

The lower fibers do this

Elevate the scapula

Retract the scapula

Depress the scapula

41

If trapezius is reflected, muscle which elevates the scapula is shown

Levator scapulae

42

This muscle fixes the scapula and extends the neck

Located superior to the rhomboids at the superior angle of the scapula

Levator Scapulae

43

Innervation of the levator scapulae

Dorsoscapular Nerve

44

If the scapulae does not move when levator scapular is contracted, what happens to the neck

If one scapulae stays fixed for unilateral contraction does what

Pulls the neck posteriorly
Extends the neck

Flexes the neck laterally to the same side, or ipsilateral side

45

Muscles shaped like a parallelogram or rhombus, lie deep to the trapezius and form broad parallel bands

Rhomboid Major and Minor

46

Form large parallel bands from vertabra to medial border of the scapulae

Rhomboids

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Minor is located superior to major, 3-4 times less wide than major

Rhomboid minor

48

Retract the scapula, can be tested by putting hands on hips and pushes with elbows posteriorly against resistance, they can be felt along medial border of the scapula

Rhomboids

49

Origin and insertion of rhomboid major and minor:

Spinous processes of vertebrae

Minor: C7-T1

Major: T2-T5

Inserts at medial border of scapula

50

Innervation of the rhomboids

Dorsoscapular Nerve

51

An action that brings the pectoral girdle anteriorly and laterally is called

Protraction

52

An action that brings the pectoral girdle posterior and medially is called

Retraction