Anatomy - extrinsic thoracic limb Flashcards
What is the origin, insertion, action, and innervation of the superficial pectoral muscle
- origin: 1st 2 sternebrae and 3rd
- insertion: greater tubercle
- action: adduct limb when it is not bearing weight or to prevent limb from being abducted when bearing weight
- innervation: ventral branch of spinal nerves C7 and C8*
What is the origin, insertion, action, and innervation of the deep pectoral muscle
- origin: ventral part of the sternum
- insertion: lesser tubercle of humerus
- action: pull the trunk cranially and extend shoulder joint & draw the limb caudally and flex shoulder joint (adduct limb)
- innervation: caudal pectoral nerves (C8, T1)
What is the origin, insertion, action, and innervation of the brachiocephalicus muscle
- origin: clavicular intersection
- insertion: cleidobrachialis - distal end of cranial border of humerus; pars cervicalis - nuchal crest; pars mastoidea - mastoid part of temporal bone with sternomastoideus muscle
- action: advance limb; extend the shoulder and draw the neck and head to side
- innervation: accessory nerve and ventral branches of cervical spinal nerves
What is the origin, insertion, action, and innervation of the sternocephalicus muscle
- origin: first sternebra
- insertion: mastoid part of temporal bone and the nuchal crest of occipital bone
- action: draw head and neck to side
- innervation: accessory nerve and ventral branches of cervical spinal nerves
What is the origin, insertion, action, and innervation of the sternohyoideus muscle
- origin: first sternebrae and first costal cartilage
- insertion: basihyoid bone
- action: pull tongue and larynx caudally
- innervation: ventral branches of cervical spinal nerves
What is the origin, insertion, action, and innervation of the sternothyroideus muscle
- origin: first costal cartilage
- insertion: caudolateral surface of the thyroid cartilage
- action: draw tongue and larynx caudally
- innervation: ventral branches of cervical spinal nerves and hypoglossal nerve
What is the origin, insertion, action, and innervation of the omotransversarius muscle
- origin: distal scapular spine
- insertion: wing of atlas
- action: advance the limb or flex the neck laterally; draw limb cranially
- innervation: accessory nerve
What is the origin, insertion, action, and innervation of the trapezius muscle
- origin: median raphe of the neck and supraspinous ligament from the level of the third cervical vertebra to the level of the ninth thoracic vertebra
- insertion: spine of the scapula
- action: to elevate and abduct the forelimb
- innervation: accessory nerve
What is the origin, insertion, action, and innervation of the rhomboideus muscle
- origin: nuchal crest of the occipital bone; the spinous process of the T4-T7
- insertion: dorsal border and adjacent surfaces of the scapula
- action: elevate the forelimb and draw the scapula against the trunk (adduct)
- innervation: ventral branches of cervical and thoracic spinal nerves
What is the origin, insertion, action, and innervation of the latissimus dorsi muscle
- origin: thoracolumbar fascia from the spinous process of the lumbar and the last seven or eight thoracic vertebrae; a muscular attachment to the last 2 or 3 ribs
- insertion: teres major tuberosity of the humerus and the teres major tendon
- action: draw the free limb caudally as in diggin; flex shoulder
- innervation: thoracodorsal nerve (C7, C8, T1)
What is the origin, insertion, action, and innervation of the serratus ventralis muscle
- origin: transverse process of last 5 cervical vertebrae and first 7 ot 8 ribs ventral to midline
- insertion: scapula (serrated face)
- action: support the trunk and depress scapula
- innervation: ventral branches of cervical spinal nerves and long thoracic nerve (C7)
what are the parts of the nuchal ligament
in dog (1 part) and horse (2 parts)
dog - funicular part
horse - funicular part and laminar part
