Extrinsic Muscles of the Thoracic Limb Flashcards
Superficial Pectoral (Descending and Transverse Pectoral) Origin Insertion Action Innervation
Origin: -D: first sternabra
-T: 2-3 sternabrae
Insertion: D & T: crest of greater tubercle of humerus
Action: -w/ weight: adducts limb
-w/o weight: Prevents abduction of limb
Innervation: spinal nerves C7 and C8
Deep Pectoral Muscle
Origin
Insertion
Action
Innervation
Origin: Ventral part of sternabrae
-Deep fascia in xiphoid cartilage (caudal end of sternum)
Insertion: -Lesser tubercle of humerus
- Aponeurosis to greater tubercle & crest
Action:-w/ weight: Pulls trunk cranially & extends shoulder joint
- w/o weight: draws limb caudally & flex shoulder joint
- Adduct limb
Innervation:
Caudal pectoral nerves (C8,T1)
Brachiocephalicus
parts?
intersection?
in cats?
Origin
Insertion
Action
Innervation
- cleidocephalicus
- contains pars
mastoideous and
cervicalis
- contains pars
- cleidobrachialis
in cats the clavicle bone is embedded in here
Origin: clavicular intersection
Inerstion: 1.Cleidocephalicus: neck
- Pars mastoideus: mastoid process of skull
- Pars cervicalis: mid-dorsal fibrous raphe of neck
- Cleidobrachialis: humerus
Action:
- advance the limb
- extend the shoulder joint
- draw the neck and head to the side
Innervation:
accessory nerve and cervical spinal nerves
Omotransversarius
Insertion
Action
Innervation
Origin:
(wing) of the atlas C1
Action:
- to advance the limb
- flex the neck laterally
Innervation:
Accessory nerve
Trapezius Parts? Where is it attached to the scapula? Action Innervation
Thoracic and cervical
Insertion: the spine of the scapula
Action: elevate and abduct the forelimb
Innervation:
Accessory nerve
Rhomboideus
Parts?
Action
Innervation
contains rhomboideus capitis, cervicis, and thoracis
Action:
- elevate the forelimb
- draw the scapula against the trunk
Innervation: cervical and thoracic spinal nerves
Latissimus Dorsi
Origin
Insertion
Action
Innervation
Origin:
- Thoracolumbar fascia from spinous process of lumbar & last 7-8 thoracic vertebrae
- Muscular attachment to last 2-3 ribs
Insertion:
- the teres major tuberosity of the humerus
- the teres major tendon
Action:
- to draw the free limb caudally (digging)
- to flex the shoulder joint
Innervation: thoracodorsal nerve (C7, C8, T1)
Serratus Ventralis
Parts Origin Insertion Action Innervation
Parts:
Serratus ventralis cervicis and thoracis
Origin:
- transverse process of the last cervical vertebrae
- the first 7 or 8 ribs ventral to their middle
Insertion: serrated face
Action:
- to support the trunk
- depress the scapula
Innervation: cervical spinal nerves and the long thoracic nerve
Thoracolmbar fascia
- deep fascia of the trunk
Linea Alba
ventral midline along a median fibrous raphe
Carotid Sheath
deep fascia that covers the common carotid artery, vagosympathetic trunk, internal jugular vein, and tracheal lymphatic trunk
Median Raphe of the neck
- longitudinal fibrous septum between the right and left epaxial muscles
- serves as attachment to cervical muscles
Sternocephalicus
Parts?
Action?
Innervation?
Pars mastoidueus and occipitalis
Action:
- draw the head and neck to the side
Innervation: accessory nerve and cervical spinal nerves
Sternohyoideus
Action?
Innervation?
Action: to pull the tongue and larynx caudally
Innervation: cervical spinal nerves
Sternothyroideus
Action?
Innervation?
Action: pull the tongue and larynx caudally
Innervation: cervical spinal nerves and hypoglossal nerve
Cutaneous Trunchi
action
innervation
platysma (thickened neck portion)
twitches skin
innervated by lateral thoracic nerve
Superficial Fascia
Deep portion of subcutaneous tissue covering body
Deep Fascia
Firmly attached to muscle
Aponeurosis
Thin sheet of tendon
Tendon vs. Ligament
tendon- dense CT (collagen)
ligament - dense fibrous connective tissue between bones, connects organs-organs/trunk
costal arch
Costal cartilages of 10-12 ribs uniting
