Extrinsic forelimb muscles (lateral)

Question 1

M. brachiocephalicus (origin, insertion & action)?

Answer 1

ORIGIN - 1. cranial Raphé of neck, 2. temporal bone
INSERTION - medial distal humerus
ACTION - draw limb forward. If leg planted, draws neck & head to the side

Question 2

M. trapezius (origin, insertion & action)?

Answer 2

ORIGIN - 1. Raphé of neck, 2. supraspinous ligament
INSERTION - spine of scapula dorsally
ACTION - elevate limb & draw it forward

Question 3

M. latissimus dorsi (origin, insertion & action)?

Answer 3

ORIGIN - 1. Lumbodorsal fascia, 2. Last 2 to 3 ribs
INSERTION - Teres tuberosity of humerus
ACTION - draws limb forward & possibly laterally support limb, draw free limb backward during flexion of shoulder joint

Question 4

M. omotransversarius (origin, insertion & action)?

Answer 4

ORIGIN - Transverse process (wing of atlas - C1)
INSERTION - distal spine of scapula ventrally
ACTION - raises scapula & moves limb forward