Extrinsic Muscles of the TL

Question 1

Superficial pectoral

Answer 1

O: first 3 sternebrae, median fibrous raphe
I: crest of the greater tubercle of the humerus
A: adduct limb (non-weight bearing), prevent abduction (weight-bearing)

Question 2

Deep pectoral

Answer 2

O: ventral part of sternum, median fibrous raphe
I: lesser tubercle of the humerus, greater tubercle of the humerus, crest of the greater tubercle of the humerus
A: pull trunk cranially when limb is advanced and fixed, extend shoulder, draw limb caudally when not supporting weight
SUBCLAVIUS IS CONSIDERED PART OF DEEP PECTORAL MUSCULATURE

Question 3

Brachiocephalicus

Answer 3

O: clavicular intersection
I: distal end of cranial humerus, middorsal fibrous raphe of the neck, mastoid part of the temporal bone
A: advance the limb, extend shoulder, draw head and neck to the side

Question 4

Omotransversarius

Answer 4

O: wing of the atlas
I: distal end of the spine of the scapula
A: advance the limb, flex the neck laterally

Question 5

Trapezius

Answer 5

O: median fibrous raphe of the neck, supraspinous ligament
I: spine of the scapula
A: elevate and abduct the limb

Question 6

Rhomboideus

Answer 6

O: base of skull, median fibrous raphe of neck, spinous processes of thoracic vertebrae
I: dorsal border of scapula
A: elevate limb, draw scapula against trunk

Question 7

Latissimus dorsi

Answer 7

O: thoracolumbar fascia, last few ribs
I: teres major tuberosity of the humerus via the teres major tendon
A: draw limb caudally (DIGGING), flex shoulder

Question 8

Serratus ventralis

Answer 8

O: ribs, transverse processes of cervical vertebrae
I: serrated face of the scapula
A: support trunk, depress scapula