The Upper Limb Revision- Muscles Of The Shoulder Region

Front 1

PECTORALIS MAJOR:Origin

Back 1

(i)Clavicular head: Anterior surface of the inner 2/3rds of the clavicle

(ii)Sternocostal head: Anterior surface of sternum and uper six ribs

Front 2

PECTORALIS MAJOR:Insertion

Back 2

Lateral crest of the intertubecular groove.

The Lower fibres are inserted deep to the upper fibres.

Front 3

PECTORALIS MAJOR:Nerve Supply

Back 3

Lateral Pectoral nerve and Medial Pectoral Nerve

Front 4

PECTORALIS MAJOR:Action

Back 4

Adducts,flexes and medially rotates the arm. If the shoulder girdle is fixed, it can be used as an accessory muscle of respiration drawing the thoracic cavity upwards.

Front 5

PECTORALIS MINOR:Origin

Back 5

3rd,4th and 5th ribs.

Front 6

PECTORALIS MINOR:Insertion

Back 6

Coracoid process of the scapula

Front 7

PECTORALIS MINOR:Nerve supply

Back 7

Medial Pectoral nerve

Front 8

PECTORALIS MINOR:Action

Back 8

Either draws the coracoid process forward and downwards or draws ribs upwards.

Front 9

SUBCLAVIUS:Origin

Back 9

Junction of first costal cartilage and bony rib

Front 10

SUBCLAVIUS:Insertion

Back 10

Undersurface of the clavicle

Front 11

SUBCLAVIUS:Nerve supply

Back 11

Subclavian nerve

Front 12

SUBCLAVIUS:Action

Back 12

Depresses the lateral end of the clavicle and stablises it too.

Front 13

SERRATUS ANTERIOR:Origin

Back 13

1st to 8th ribs. Arises by digitations from the anterior ribs from the anterior ends.

Front 14

SERRATUS ANTERIOR:Insertion

Back 14

The Vertebral border of the scapula.

Front 15

SERRATUS ANTERIOR:Nerve supply

Back 15

Nerve to serratus anterior. (The long thoracic Nerve)

Front 16

SERRATUS ANTERIOR:Action

Back 16

Draws the scapula around the chest when pushing with one arm flexed.

Front 17

LATISSIMUS DORSI:Origin

Back 17

(i) Vertebral spines, T7-S2

(ii)Posterior part of iliac crest

(iii)Slips from 9th and 12th ribs

Front 18

LATISSIMUS DORSI:Insertion

Back 18

Intertubecular groove of the humerus

Front 19

LATISSIMUS DORSI:Nerve supply

Back 19

Thoracodorsal nerve

Front 20

LATISSIMUS DORSI:Action

Back 20

Adducts, medially roates and extends the arm.

Front 21

LEVATOR SCAPULAE:Origin

Back 21

Tubercles of the transverse processes of the 1st and 2nd cervical vertebrae.

Front 22

LEVATOR SCAPULAE:Insertion

Back 22

Vertebral border of scapula

Front 23

LEVATOR SCAPULAE:Nerve Supply

Back 23

C3 and C4 and dorsal scapular nerve(C5)

Front 24

LEVATOR SCAPULAE:Action

Back 24

Raises the scapula and supports the upper limb.

Front 25

TRAPEZIUS:Origin

Back 25

(i)External occipital protuberance and inner 1/3rd of superior nuchal line

(ii)Ligamentum nuchae running from skull to spine.

(iii)Vertebral spines from C7-T12 and supraspinous ligaments between

Front 26

TRAPEZIUS:Insertion

Back 26

(i)Upper border of the spine of the scapula

(ii)Inner border of the acromion

(iii)Posterior broder of the 1/3rd of the clavicle

Front 27

TRAPEZIUS:Nerve supply

Back 27

XI accessory nerve

Front 28

TRAPEZIUS:Action

Back 28

Upper fibres pull the scapula and clavicle upwards.

Lower fibres pull the scapula downwards.

Whole muscle pulls the scapula towards the midline.

The Trapezius is also used to rotate the scapula as when raising the arm above the head.

The upper fibres also support the weight of the upper limb.

Front 29

DELTOID:Origin

Back 29

Outer 1/3rd of the anterior surface of the clavicle.

Outer border of the acromion and lower border of the spine of the scapula.

Front 30

DELTOID:Insertion

Back 30

Deltoid tuberosity of the humerus

Front 31

DELTOID:Nerve supply

Back 31

Axillary Nerve

Front 32

DELTOID:Action

Back 32

Abducts the humerus.

The Anterior fibres acting alone flex the arm.

The posterior fibres acting alone extend the arm.

Front 33

SUPRASPINATUS: Origin

Back 33

Supraspinous fossa of the scapula

Front 34

SUPRASPINATUS: Insertion

Back 34

Greater tubercle of the humerus (the uppermost facet).

Front 35

SUPRASPINATUS:Nerve supply

Back 35

Suprascapular nerve. C5+C6 forming the upper trunk

Front 36

SUPRASPINATUS:Action

Back 36

Abducts the humerus.

Front 37

INFRASPINATUS:Origin

Back 37

Infraspinous fossa of the scapula

Front 38

INFRASPINATUS:Insertion

Back 38

Greater tubercle of the humerus (middle facet)

Front 39

INFRASPINATUS:Nerve supply

Back 39

Suprascapular nerve

Front 40

INFRASPINATUS:Action

Back 40

Lateral rotator of the humerus.

Fixator of the head of the humerus

Front 41

TERES MINOR:Origin

Back 41

Middle part of the lateral border of the scapula

Front 42

TERES MINOR:Insertion

Back 42

Greater tubercle of the humerus. (lowermost facet)

Front 43

TERES MINOR:Nerve supply

Back 43

Axillary nerve

Front 44

TERES MINOR:Action

Back 44

Lateral rotator of the humerus.Fixator of the head of the humerus

Front 45

SUBSCAPULARIS:Origin

Back 45

Subscapular fossa of the scapula

Front 46

SUBSCAPULARIS:Insertion

Back 46

Lesser tubercle of the humerus

Front 47

SUBSCAPULARIS:Nerve supply

Back 47

Subscapular nerves

Front 48

SUBSCAPULARIS:Action

Back 48

Medial rotator of the humerus

Front 49

TERES MAJOR:Origin

Back 49

Lower part of the lateral border and the inferior angle of the scapula.

Front 50

TERES MAJOR:Insertion

Back 50

Medial crest of the intertubercular groove of the humerus

Front 51

TERES MAJOR: Nerve supply

Back 51

Lower subscapular nerve

Front 52

TERES MAJOR:Action

Back 52

Adducts and medially rotates the humerus

Front 53

BICEPS BRACHII:Origin

Back 53

Long head arises form the scapula just above the glenoid cavity.

Short head arises form the tip of the coracoid process of the scapula.

Front 54

BICEPS BRACHII:Insertion

Back 54

Posterior part of the tuberosity of the radius and through the bicipital aponeurosis to the deep fascia of pronator teres

Front 55

BICEPS BRACHII: Nerve supply

Back 55

Musculocutaneous

Front 56

BICEPS BRACHII:Action

Back 56

Flexes the elbow and supinates the forearm

Front 57

CORACOBRACHIALIS:Origin

Back 57

Tip of the coracoid process of the scapula

Front 58

CORACOBRACHIALIS:Insertion

Back 58

Middle of the shaft of the humerus on medial side

Front 59

CORACOBRACHIALIS: Nerve supply

Back 59

Musculocutaneous nerve

Front 60

CORACOBRACHIALIS:Action

Back 60

Flexes and adducts the shoulder.

Front 61

BRACHIALIS:Origin

Back 61

Lower 2/3rds of anterior surface of the humerus

Front 62

BRACHIALIS:Insertion

Back 62

Ulna, in front of the coracoid process

Front 63

BRACHIALIS: Nerve supply

Back 63

Musculocutaneous nerve

Front 64

BRACHIALIS: Action

Back 64

Flexor of the elbow joint

Front 65

TRICEPS:Origin

Back 65

Long Head- From the scapula BELOW the glenoid cavity.

Lateral Head- From the ridge on the humerus below the greater tubercle

Medial Head-From the posterior surface of humerus below the spiral groove

Front 66

TRICEPS:Insertion

Back 66

Olecranon of the ulna

Front 67

TRICEPS: Nerve supply

Back 67

Radial Nerve

Front 68

TRICEPS:Action

Back 68

Weak extensor of the elbow