Cervical Structures, Hypaxial and Epaxial mm. Flashcards
Structures in the neck
Trachea - located ventrally
Esophagus - located dorsally
Larynx - voice box; articulates with cranial portion of trachea
Trachea
Cartilage rings - C shaped, incomplete dorsally
Tracheal ligament - courses between tracheal rings
Trachealis muscle - dorsal part of trachea, completes cartilage rings, smooth muscle
Thyroid gland
Located in lateral aspect of trachea, caudal to larynx
Can be situated more caudally in cats
Produces thyroid hormones and calcitonin
Parathyroid gland
2 sets - 1 internal, 1 external
Produces parathyroid hormone
Carotid sheath components
Common carotid artery
Internal jugular vein
Vagosympathetic trunk (vagus n., sympathetic trunk)
Recurrent laryngeal n.
Tracheal lymphatic duct
Epaxial muscles
Located dorsal to transverse processes of vertebrae
Extensors of vertebral column
Hypaxial muscles
Located ventral to transverse processes of vertebrae
Includes muscles of thoracic and abdominal walls
Longus capitis m.
O: caudal portions of transverse vertebrae of C2-C6
I: Muscular tubercle of the basioccipital bone of the skull
N: Ventral branches of cervical spinal nerves
A: Flex atlanto-occipital joint and draw neck downward
Longus colli m.
Cervical portion
O: Ventral surfaces of T1-T6
I: Transverse processes of C6-7
Thoracic portion
O: Ventral border of transverse processes of C3-6
I: Ventral crest of the preceding vertebra; cranial segment inserts on the ventral tubercle of the atlas
N: Ventral branches of cervical and thoracic spinal nerves
A: Draw the neck downward
Inspiratory muscles
Muscles that draw the ribs cranially and outward
-Scalenus m.
-Serratus dorsalis cranialis m.
-Rectus thoracis m.
-External intercostal mm.
Expiratory muscles
Muscles that draw the ribs caudally and inward
-Serratus dorsalis caudalis m.
-Internal intercostal mm.
Innervation of hypaxial mm.
Longus capitis m.- Ventral branches of cervical spinal nerve
Longus colli and scalenus mm. - Ventral branches of thoracic spinal nerve
Serratus dorsalis cranialis, serratus dorsalis caudalis, rectus thoracis, internal and external intercostal mm. - intercostal nn.
Epaxial mm. general innervation and actions
N: Dorsal brs. of cervical, thoracic, lumbar, sacral, and caudal spinal nn.
A: Extensors of the vertebral column (neck, trunk, tail); produce lateral movements when acting on one side
Iliocostalis system
Most lateral system of epaxial mm.
Longissimus system
Located medial of the iliocostalis system of the epaxial mm.
