Extrinsic Muscles of the Thoracic Limb Flashcards
Which muscle fuses with Omotransversarius in horses?
Brachiocephalicus m.
Cleidocephalicus m.
Attachments:
(Carnivores) Pars mastoidea and Pars cervicalis- clavicular intersection, median raphe and nuchal ligament, and mastoid process of temporal bone
(Horse) Pars mastoidea- clavicular intersection and mastoid process of temporal bone
(Ruminants) Pars mastoidea and Pars occipitalis- clavicular intersection, occipital bone, and mastoid process of the temporal bone
Actions:
Advance the limb
Extend the shoulder
Draw the neck and head down or to the sides
Innervation:
Accessory n. & Cervical spinal n.
Blood Supply:
Superficial cervical a. and v.
Cleidocephalicus m.
(Horse)
Attachments:
Pars mastoidea- clavicular intersection and mastoid process of temporal bone
Actions:
Advance the limb
Extend the shoulder
Draw the neck and head down or to the sides
Innervation:
Accessory n.,
Cervical spinal n.
Blood Supply:
Superficial cervical a. and v.
Trapezius m.
Attachments:
Pars cervicalis
Pars thoracis
scapular spine, median raphe, and nuchal ligament
Actions:
Elevate the forelimb
Abduct the forelimb
Innervation:
Accessory n. (cranial n. XI)
Blood Supply:
Superficial cervical a. and v.
Rhomboideus m.
(Carnivores)
Attachments:
Rhomboideus capitis, Rhomboideus cervicis, & Rhomboideus thoracis- Median raphe and nuchal crest, spinous processes of cervical and thoracic vertebrae, and dorsal border of scapular cartilage
Actions:
Elevate the forelimb
Draw the scapula against the trunk
Innervation:
Cervical spinal n. (ventral branches)
Thoracic spinal n. (ventral branches)
Blood Supply:
Various aa. and vv.
Serratus ventralis m.
Attachments:
Serratus ventralis cervicis and serratus ventralis thoracis- serrated face of the scapula & cervical vertebrae and ribs
Actions:
Suspends the trunk
Depresses the scapula
Innervation:
Long thoracic n.,
Spinal n. (ventral branches)
Blood Supply:
Thoracodorsal a. and v.
Pectoral Muscles
Attachments:
Superficial pectorals (descending and transverse)- sternum and fibrous raphe (deep fascia) & humeral crest and greater tubercle
Deep pectorals- sternum and fibrous raphe (deep fascia) & lesser tubercle and brachial fascia
Actions:
Supports the trunk
Adducts the limb
Draws the limb forward and backward
Extensor of the shoulder joint
Innervation:
Cranial pectoral n.
Caudal pectoral n.
Blood Supply:
External thoracic aa. and vv.
Lateral thoracic aa. and vv.
Omotransversarius m.
Attachments:
Transverse process (wing) of atlas & the scapular spine
** Need to reflect Brachiocephalicus m. in dogs to see omotransversarius m.
*Fuses with the brachiocephalicus m. in horses*
Actions:
Advance the limb
Flex the neck laterally
Innervation:
Ventral branches of servical spinal n.
Blood Supply:
Various aa. and vv.
Brachiocephalicus m.
(2 parts)
Attachments:
Cleidocephalicus- (O) clavicular intersection and species specific
Cleidobrachialis- (O) clavicular intersection and (I) cranial border of the humerus
Actions:
Advance the limb
Extend the shoulder
Draw the neck and head down or to the sides
Innervation:
Accessory & Cervical spinal nn.
Blood Supply:
Superficial cervical a. and v.
Rhomboideus m.
(Horses & Ruminants)
Attachments:
Rhomboideus cervicis & Rhomboideus thoracis- (O) spinous processes of cervical and thoracic vertebrae, and (I) dorsal border of scapular cartilage
Actions:
Elevate the forelimb
Draw the scapula against the trunk
Innervation:
Cervical spinal n. (ventral branches),
Thoracic spinal n. (ventral branches)
Blood Supply:
Various aa. and v.
Cleidocephalicus m.
(Ruminants)
Attachments:
Pars mastoidea
Pars occipitalis
(O) clavicular intersection (I) occipital bone (I) mastoid process of the temporal bone
Actions:
Advance the limb
Extend the shoulder
Draw the neck and head down or to the sides
Innervation:
Accessory n.
Cervical spinal n.
Blood Supply:
Superficial cervical a. and v.
Cleidocephalicus m.
(Dogs)
Attachments:
Pars mastoidea and Pars cervicalis- clavicular intersection, median raphe and nuchal ligament, and mastoid process of temporal bone
Actions:
Advance the limb
Extend the shoulder
Draw the neck and head down or to the sides
Innervation:
Accessory n. & Cervical spinal n.
Blood Supply:
Superficial cervical a. and v.
Latissimus dorsi m.
(Digging muscle)
Attachments:
(O) Thoracolumbar fascia & (I) tuberosity of teres major
Actions:
Draw the limb caudally
Flex the shoulder joint
Innervation:
Thoracodorsal n.
Blood Supply:
Thoracodorsal a. and v.
Lateral thoracic a.
Cutaenous trunchi m.
Blood Supply:
Lateral thoracic a. and v.
Innervation:
Lateral thoracic n.
Deep pectoral m.
Blood Supply:
External thoracic a. and v.
Innervation:
Caudal pectoral n.
