Lecture 22 - Pectorial Girdle and Arm Muscles

Question 1

Shoulder muscles

Answer 1

Connect scapula, clavicle, body wall to the humerus

Move the shoulder joints

Question 2

Shoulder muscles list

Answer 2

Deltoid
Pectoralis major
Latissimus dorsi
Teres major

Question 3

Deltoid origin and insertion

Answer 3

Origin:
• Scapula, Clavicle
Insertion:
• Humerus

Question 4

Deltoid is innervated by the

Answer 4

axillary nerve

Question 5

Deltoid and function on arm

Answer 5

Deltoid has 3 different fibres, looks like an inverted triangle, located in the upper part of the arm

• Anterior fibres = flex (flexion of the shoulder joint)
• Middle fibres = abduct
• Posterior fibres = extend

Question 6

Pectoralis major origin and insertion

Answer 6

Origin:
• Clavicle, Sternum, costal cartilages (attaches proximally)
Insertion:
• Humerus (attaches distally to the humerus)

Question 7

Pectoralis major function

Answer 7

• Flexion, adduction and medial rotation of arm

on anterior surface which is why it does dlextion

Question 8

Latissimus dorsi origin and insertion

Answer 8

It is quite a light muscle

Origin:
• Spinous processes of the vertebrae, iliac crest, inferior ribs
Insertion:
• Humerus (attaches distally)

Question 9

Latissimus dorsi function

Answer 9

• Extend, adduct (brings the shoulder joint back to the midline), medially rotate arm

connects to shoulder joint therefore has action on it

Question 10

Teres major origin and insertion

Answer 10

Origin:
• Inferior angle of scapula
Insertion:
• Humerus

Question 11

Teres major function

Answer 11

Function:

• Extend, adduct, medially rotate arm

Question 12

Shoulder muscles from most anterior to most posterior

Answer 12

Pectoralis major
Long tendon of biceps
Latissimus dorsi
Teres major

(MLLM)

Question 13

Pectorial girldle muscles list

Answer 13

Trapezius
Levator scapulae
Rhomboids

Question 14

Trapezius origin and insertion

Answer 14

Origin:
• Occipital bone
Insertion:
• Clavicle
• Scapula (spine & acromion)

Question 15

Function on scapula of trapezius

Answer 15

Function on scapula:
• Superior fibres = Elevate scapula
• Horizontal fibres = Retraction of the scapula 
 • Inferior fibres = Depress the scapula
• Rotation

Question 16

Levator scapulae origin and insertion

Answer 16

Origin:
• Transverse processes of cervical vertebrae
Insertion:
• Superior angle of scapula

Question 17

Levator scapulae function

Answer 17

• Elevate scapula

Question 18

Rhomboids

Answer 18

4 sided muscle for retraction, more than one rhomboid (minor and major - names are not examinable)

Question 19

Rhomboids origin and insertion

Answer 19

Origin:
• Spinous processes of the vertebrae
Insertion:
• Medial border of scapula

Question 20

Rhomboids function

Answer 20

Function:

• Retract scapula

Question 21

Number of rotator cuff muscles

Answer 21

4

Question 22

Rotator cuff muscles list

Answer 22

Supraspinatus
Infraspinatus
Teres minor
Subscapularis

(Teres MAJOR is not a part of the rotator cuff)

Question 23

General function of rotator cuff muscles

Answer 23

General function:
• To support glenohumeral joint
• All rotate humerus, except for supraspinatus

Question 24

What do rotator cuff muscles connect?

Answer 24

connects scapula and clavicle to the humerus

Question 25

SITS stands for what group of muscles and also list the muscles

Answer 25

Rotator cuff muscles Supraspinatus Infraspinatus Teres minor Subscapularis

Question 26

Rotator cuff muscles that are on the posterior side of the scapula

Answer 26

Supraspinatus Infraspinatus Teres minor

Question 27

Rotator cuff muscles that are on the anterior side of the scapula

Answer 27

Subscapularis

Question 28

Attachments of rotator cuff muscles

Answer 28

All attach to the greater tubercle of the humerus, except for subscapularis (attaches to the lesser tubercle) greater tubercle is more lateral Lesser tubercle is more medial therefore helps more with medial rotaiton

Question 29

Function of rotator cuff muscles

Answer 29

* Supraspinatus initiates abduction * Infraspinatus and Teres minor laterally rotate humerus * Subscapularismedially rotates humerus

Question 30

Supraspinatus function

Answer 30

Supraspinatus initiates abduction (helps to initiate, only about 10 degrees, deltoids then takes over)

Question 31

Infraspinatus and Teres minor function

Answer 31

Infraspinatus and Teres minor laterally rotate humerus

Question 32

Subscapularis function

Answer 32

Subscapularis medially rotates humerus

Question 33

Rotator cuff impingement

Answer 33

impingement is about tendon ``` Implications: • Inflammation (Tendinitis, bursitis (inflammation of burse which is a pouch of synovial membrane)) • Swelling & pain • Impairs movement • Possible rupture of tendons • Capsular weakness ``` Remember: Tendons and ligaments lack blood vessels (Difficulty healing)

Question 34

Arm muscles

Answer 34

Biceps brachii, brachialis, coracobrachialis, triceps brachii

Question 35

Anterior compartment of arm muscles

Answer 35

• Flexors • Muscle: Biceps brachii, Brachialis, Coracobrachialis • Nerve: MusculoCutaneous nerve

Question 36

Posterior compartment of arm muscles

Answer 36

* Extensors | * Muscle: triceps brachii • Nerve: radial nerve

Question 37

Nerve of the anterior comparment of arm mucles

Answer 37

Musculocutaneous nerve

Question 38

Nerve fo the posterior compartment of arm muscles

Answer 38

Radial nerve

Question 39

______ in anterior comparment of arm muscles

Answer 39

flexors

Question 40

_______ in posterior compartment of arm muscles

Answer 40

extensors

Question 41

Muscles of the anterior comparment of the arm

Answer 41

Biceps brachii Brachialis Coracobrachialis

Question 42

Muscles of the posterior compartment of the arm

Answer 42

Triceps brachii

Question 43

Triceps brachii

Answer 43

Only posterior one | 3 headed muscle - long, lateral and medial head (medial head is deep to the long head)

Question 44

Origin and insertion of triceps brachii

Answer 44

Origin: • Long head: infraglenoid tubercle of scapula • Medial head: humerus • Lateral head: humerus Insertion: • Olecranon of ulna (common attachment of all three heads here)

Question 45

Long head of triceps brachii origin

Answer 45

Long head: infraglenoid tubercle of scapula

Question 46

Medial head of triceps brachii origin

Answer 46

Medial head: humerus

Question 47

Lateral head of triceps brachii origin

Answer 47

Lateral head: humerus

Question 48

Function of triceps brachii

Answer 48

Extend arm and forearm (because posterior) Long head is the only one that attaches at the shoulder joint and the other 2 attach to the arm All heads cause = Elbow joint extension Long head = SJ extension

Question 49

Biceps brachii

Answer 49

Anterior | 2 heads - long and short head

Question 50

Biceps brachii origin and insertion

Answer 50

Origin: • Long head: supraglenoid tubercle of scapula • Short head: coracoid process Insertion: • Radial tuberosity

Question 51

Long head of biceps brachii origin

Answer 51

Long head: supraglenoid tubercle of scapula

Question 52

Short head of biceps brachii origin

Answer 52

Short head: coracoid process

Question 53

Biceps brachii function

Answer 53

Function: • Flex arm & forearm • Supinate forearm SJ flexion, EJ flexion, supination of forearm

Question 54

Bicipital aponeuriosis

Answer 54

Median nerve and brachial artery run under this Need to extend elbow to feel pulse to move this out of the way brachial artery goes under this then splits

Question 55

Coracobrachialis origin and insertion

Answer 55

Origin: • Coracoid process Insertion: • Humerus

Question 56

Coracobrachialis function

Answer 56

Function: • Flex arm • Adduct arm SJ flexion - doesnt cross EJ so no function

Question 57

Brachialis origin and insertion

Answer 57

arm to elbow Origin: • Humerus Insertion: • Coronoid process of Ulna

Question 58

Brachialis function

Answer 58

• Flex forearm EJ flexion - does not cross the SJ so no function here

Question 59

Brachial artery

Answer 59

* Continuation of axillary artery * Runs on medial forearm * Divides into radial and ulnary arteries deep veins match

Question 60

Arterial supply to the upper limb

Answer 60

Subclavian to axillary to brachial to radial and ulnar artery

Question 61

Arm veins

Answer 61

* Brachial veins is deep, and run with brachial artery * Two large superficial veins are cephalic and basilic veins * The median cubital vein crosses between them

Question 62

Median cubital vein

Answer 62

cross between the cephalic and basilic veins Connecting branch between the two Blood is usually taken from here

Question 63

Innervation of anterior arm muscles

Answer 63

Musculocutaneous nerve (pierces through coracobrachialis, MC in arm itself is between brachialis and biceps) MC supplies BBC MusculoCutaneous supplies Biceps, Brachialis, Coracobrachialis

Question 64

MC supplies BBC

Answer 64

MusculoCutaneous supplies Biceps, Brachialis, Coracobrachialis

Question 65

Innervation of posterior arm muscles

Answer 65

Radial nerve