Extrinsic Muscles - Attachments and Actions

Question 1

Superficial pectoral muscles - names

Answer 1

descending (cranial)

transverse (caudal)

Question 2

superficial pectoral muscles origin –> insertion

Answer 2

first 2 sternebrae –> greater tubercle of humerus

Question 3

superficial pectoral muscles action

Answer 3

adduct forelimb

Question 4

deep (ascending) pectoral origin –> insertion

Answer 4

sternum –> greater and lesser tubercles of humerus

Question 5

deep pectoral action

Answer 5

adduct and pull limb caudally, flexes shoulder

Question 6

parts of the brachiocephalicus

Answer 6

cleidobrachialis
cleidomastoideus
cleidocervicalis

Question 7

brachiocephalicus origin

Answer 7

clavicular intersection (all 3 parts)

Question 8

brachiocephalicus insertions (all 3 parts)

Answer 8

brachial: distal humerus, cranial border
cervical: mid-dorsal fibrous raphe of neck
mastoid: mastoid process of temporal bone

Question 9

brachiocephalicus action

Answer 9

advance limb, turn head to the side, extend shoulder

Question 10

parts of the sternocephalicus

Answer 10

sternomastoideus

sterno-occipitalis

Question 11

sternocephalicus origin –> insertion

Answer 11

first sternebra –> mastoid process of temporal bone, nuchal crest of the occipital bone

Question 12

sternocephalicus action

Answer 12

turn head and neck to side

Question 13

sternohyoideus origin –> insertion

Answer 13

first sternebrae and costal cartilage –> basihyoid bone

Question 14

sternohyoideus action

Answer 14

pull tongue and larynx caudally

Question 15

sternothyroideus origin –> insertion

Answer 15

first costal cartilage –> thyroid cartilage (of larynx)

Question 16

sternothyroideus action

Answer 16

pull tongue and larynx caudally

Question 17

omotransversarius origin –> insertion

Answer 17

acromion of scapula –> transverse process of atlas

Question 18

Omotransversarius action

Answer 18

advance limb, turn neck to side

Question 19

Trapezius origin –> insertion

Answer 19

median raphe of neck, supraspinous ligament –> spine of scapula

Question 20

Trapezius action

Answer 20

elevate, abduct forelimb

Question 21

Rhomboideus origin –> insertion

Answer 21

median raphe of neck, nuchal crest of occipital bone –> dorsal border of scapula

Question 22

rhomboideus action

Answer 22

elevate forelimb

Question 23

Latissimus dorsi origin –> insertion

Answer 23

spinous processes of thoracic and lumbar vertebrae, thoracolumbar fascia –> teres major tuberosity

Question 24

Latissimus dorsi action

Answer 24

draw limb caudally, flex shoulder

Question 25

Serratus ventralis origin –> insertion

Answer 25

transverse processes of cervical vertebrae, middle of ribs

Question 26

Serratus ventralis action

Answer 26

support trunk, depress scapula