Thoracic Limb - Origin, Termination, and Action by Muscle

Question 1

What are the origin, insertion, and action of the superficial pectoral?

Answer 1

origin: sternum
termination: crest of greater tubercle and cranial humeral border
action: adduct thoracic limb

Question 2

What are the origin, insertion, and action of the deep pectoral?

Answer 2

origin: sternum
termination: greater and lesser tubercles of humerus
action: adduct thoracic limb and pull it caudally

Question 3

What are the attachments and action of the brachiocephalicus?

Answer 3

attachments: distal cranial humerus, temporal bone, dorsal midline of neck
action: pull thoracic limb cranially, depress head and neck, and pull head and neck laterally

Question 4

What are the origin, termination, and action of the omotransversarius?

Answer 4

origin: wing of atlas
termination: distal spine of scapula
action: pull thoracic limb cranially, depress head and neck, and pull head and neck laterally

Question 5

What are the origin, termination, and action of the trapezius?

Answer 5

origin:
-cervical part: dorsal neck
-thoracic part: dorsal thorax
termination: spine of scapula
action: elevate thoracic limb

Question 6

What are the origin, termination, and action of the rhomboideus?

Answer 6

origin: dorsal thorax, dorsal neck, and occipital bone
termination: dorsal border of scapula
action: elevate thoracic limb

Question 7

What are the origin, termination, and action of the serratus ventralis?

Answer 7

origin: cervical vertebrae and ribs/thoracic wall
termination: serrated face of scapula
action: support trunk

Question 8

What are the origin, termination, and action of the latissimus dorsi?

Answer 8

origin: thoracolumbar fascia
termination: teres major tuberosity
action: draw thoracic limb caudally, flex humeral joint, and extend humeral joint

Question 9

What are the origin, termination, and action of the sternocephalicus?

Answer 9

origin: sternum
termination: temporal bone and occipital bone
action: depress head and neck and draw head and neck laterally

Question 10

What are the origin, termination, and action of the sternohyoideus?

Answer 10

origin: sternum
termination: basihyoid bone
action: pull tongue and larynx caudally

Question 11

What are the origin, termination, and action of the sternothyroideus?

Answer 11

origin: sternum
termination: thyroid cartilage
action: pull tongue and larynx caudally

Question 12

What are the origin, termination, and action of the deltoideus?

Answer 12

origin: spine of scapula and acromion
termination: deltoid tuberosity of humerus
action: flex humeral joint

Question 13

What are the origin, termination, and action of the supraspinatus?

Answer 13

origin: supraspinous fossa of scapula
termination: greater tubercle of humerus
action: extend humeral joint

Question 14

What are the origin, termination, and action of the infraspinatus?

Answer 14

origin: infraspinous fossa of scapula
termination: greater tubercle of humerus
action: flex humeral joint and abduct thoracic limb humeral joint

Question 15

What are the origin, termination, and action of the teres minor?

Answer 15

origin: caudal border of scapula
termination: teres minor tuberosity of humerus
action: flex humeral joint

Question 16

What are the origin, termination, and action of the subscapularis?

Answer 16

origin: subscapular fossa of scapula
termination: lesser tubercle of humerus
action: adduct thoracic limb at humeral joint

Question 17

What are the origin, termination, and action of the teres major?

Answer 17

origin: caudal border of scapula
termination: teres major tuberosity of humerus
action: flex humeral joint

Question 18

What are the origin, termination, and action of the coracobrachialis?

Answer 18

origin: coracoid process of scapula
termination: crest of lesser tubercle of humerus
action: adduct thoracic limb at shoulder

Question 19

What are the origin, termination, and action of the biceps brachii?

Answer 19

origin: supraglenoid tubercle
termination: radial and ulnar tuberosities
action: flex cubital joint and extend humeral joint

Question 20

What are the origin, termination, and action of the brachialis?

Answer 20

origin: brachial groove of humerus
termination: proximal radius/ulna
action: flex cubital joint

Question 21

What are the origin, termination, and action of the triceps brachii?

Answer 21

origin: caudal border of scapula (long head) and proximal humerus
termination: tuber olecrani
action: extend cubital joint and flex humeral joint (long head)

Question 22

What are the origin, termination, and action of the extensor carpi radialis?

Answer 22

origin: lateral epicondyle of humerus
termination: dorsal based of 2nd and 3rd metacarpals
action: extend carpal joints

Question 23

What are the origin, termination, and action of the common digital extensor?

Answer 23

origin: lateral epicondyle of humerus
termination: extensor processes of distal phalanges
action: extend carpal and digital joints

Question 24

What are the origin, termination, and action of the lateral digital extensor?

Answer 24

origin: lateral epicondyle of humerus
termination: distal/middle/proximal phalanges of lateral digits
action: extend carpal and digital joints of lateral digits

Question 25

What are the origin, termination, and action of the extensor carpi ulnaris (ulnaris lateralis)?

Answer 25

origin: lateral epicondyle of humerus
termination: accessory carpal bone and lateral base of 5th metacarpal
action: flex carpal joints and abduct manus

Question 26

What are the origin, termination, and action of the supinator?

Answer 26

origin: lateral epicondyle of humerus
termination: body of radius
action: supinate manus

Question 27

What is the action of the abductor pollicis longus?

Answer 27

abduct first digit

Question 28

What are the origin, termination, and action of the flexor carpi radialis?

Answer 28

origin: medial epicondyle of humerus
termination: palmar base of 2nd and 3rd metacarpals
action: flex carpal joints

Question 29

What are the origin, termination, and action of the flexor carpi ulnaris?

Answer 29

origin: medial epicondyle and olecranon
termination: accessory carpal bone
action: flex carpal joints

Question 30

What are the origin, termination, and action of the superficial digital flexor?

Answer 30

origin: medial epicondyle of humerus
termination: palmar aspect of middle phalanges
action: flex carpal, metacarpophalangeal, and proximal interphalangeal joints

Question 31

What are the origin, termination, and action of the deep digital flexor?

Answer 31

origin: medial epicondyle of humerus, radius, ulna
termination: flexor tubercles of distal phalanges
action: flex carpal and digital joints

Question 32

What are the origin, termination, and action of the pronator teres?

Answer 32

origin: medical epicondyle of humerus
termination: medial body of radius
action: pronation of manus

Question 33

What are the attachments and action of the pronator quadratus?

Answer 33

attachments: apposed surfaces of radius and ulna
action: pronation of manus