Anatomy - Thoracic Limb Extrinsic Muscles

what are extrinsic muscles?

muscles that have one attachment to the appendicular skeleton and one to the axial skeleton

what is the role of the extrinsic muscles?

to attach the forelimb to the trunk

transfer weight to the forelimb

stabilize the scapula

what 4 muscles are attached to the humerus?

1. brachiocephalicus 2. latissimus dorsi 3. superficial pectoral 4. deep pectoral

what 4 regions is the brachiocephalicus divided into?

1. cleidocephalicus 2. cleidobrachialis 3. pars masoidea 4. pars cervicalis

do dogs have a clavical?

no, it's diminished. Possibly seen as a band divided the brachiocephalicus

what are the 4 attachments to the scapula?

1. omotransversarius 2. trapezius 3. rhomboideus 4. serratus ventralis

what does the cutaneous trunci do?

twitches the skin

where are sq injections given?

in the space under the skin

what does the brachiocephalicus do?

advance the limb and extend the shoulder

what does the trapezius do?

acts to elevate and abduct the limb

what does the rhomboideus do?

elevates the limb

what does the omotransversarius do?

advances the limb forward

what do the pectorals do?

a lot, depending if the animal is bearing weight or not. But mainly to adduct the limb

what does the latissumus dorsi do?

draws the limb caudally (a dog digging) and flexes the shoulder

what does the serratus ventralis do?

acts as a sling to support the trunk

The superficial pectoral and cleidobrachialis part of the brachiocephalicus extend below the elbow and terminate on the ulna. Why?

grooming

what does the sternocephalicus split into and what does it do?

mastoid and occipital parts. Combined action pulls the head/neck to the side

when is the sternohyoideus important clinically?

when performing a tracheostomy

what do the sternohyoideus and sternothyroideus do?

pull the tongue and larynx caudally.

name this muscle

brachiocephalicus

name this muscle

latissumus dorsi

name this muscle. what species is it?

superficial pectoral. feline, cats have 3

name this muscle. what species is it?

superficial pectoral. canine, dogs have 2

name the lower muscle

deep pectoral

name this muscle

omotransversarius

name this muscle

trapezius

name this muscle

rhomboideus

name this muscle

serratus ventralis