Katerina Kyprianou

    ◦

Muscles

SCM ◦

Arteries

Carotid arteries ◦

Veins

IJV ◦

Nerves

Vagus

      Anterior boundary: ◦ Median line of the neck Posterior boundary: ◦ Anterior bordrer of the SCM Superior boundary: ◦ Inferior border of the mandible Apex: ◦ Jugular notch Roof: ◦ platysma Floor: ◦ Pharynx , larynx, thyroid gland

Attachments:  Origin  ◦ ◦ ◦ mastoid process of temporal bone Superior nuchal line Insertion Sternal head ◦  Anterior surface of manubrium Clavicular head  ◦ ◦  Superior surface of medial 1/3 of clavicle Innervation Spinal accessory nerve (motor) C2 & C3

  ◦ ◦ ◦ ◦ ◦ ◦

Unilateral contraction

Tilts head to the same side Rotates head so that head is turned superiorly to the other side

Bilateral contraction

Extends neck (antlanto-occipital joints) Flexes superior cervical vertebrae Extends superior cervical vertebrae while flexing inferior vertebrae - chin is thrust forward Elevate manubrium & medial end of clavicles – assisting in respiration

1.

2.

◦ 3.

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Common carotid artery Internal jugular vein

Located more laterally

Vagus nerve

Located posteriorly

 ◦ ◦ ◦

Common carotid

Right: begins at bifurcation of brachiocephalic trunk Left: arises as left common carotid from aorta Bifurcates at level of: thyroid cartilage

  External carotid ◦ Supply most of structures external to cranium ◦ ◦ ◦ Runs: between neck of mandible and & lobule of auricle Embedded in parotid gland Terminal branches: superficial temporal & maxillary aa Internal carotid ◦ Direct continuation of common carotid ◦ ◦ ◦ ◦ No branches in neck Enter cranium through carotid canals – main arteries of the brain Carotid sinus – proximal part of internal carotid Carotid body – between internal & external

   Largest vein in neck Drains blood from: anterior face, cervical viscera & deep muscles of the neck Begins at: jugular foramen as a continuation of the sigmoid sinus

   ◦ Runs inferiorly through the neck in the carotid sheath Leaves the anterior cervical region by passing deep to the SCM Unites with the subclavian to form the brachiocephalic Posterior to the sternal end of the clavicle

    Exit cranium through jugular foramen Pass through the carotid sheath Right vagus: Passes anterior to the first part of the subclavian aa and posterior to the brachiocephalic vein ans SC joint to enter the thorax Left vagus: descends between left common carotid & left subclavian aa & posterior to SC joint to enter thorax

     Arise from the vagus nerves R & L have the same distribution but recur over different structures Right: loops inferior to the right subclavian aa Left: Loops inferior to the arch of the aorta Both ascend superiorly