This section describes the neck and its structures.

The Neck

Outline

• muscles
• arteries
• veins
• lymphatics
• triangles
• salivary glands
• cervical plexus, ansa cervicalis

Muscles of the neck

http://www.bartleby.com/107/illus385.html

http://www.bartleby.com/107/illus378.html

Superficial cervical

• Muscle: platysma
• Origin: fascia overlying the pectoralis major and the deltoid muscles
• Insertion: interior border of the mandible and skin of the lower face
• Action: draws corners of mouth down, aids in depression of mandible
• Innervation: cervical branch of facial nerve (VII) Artery: facial a. #13; 13;

Lateral cervical muscles

• Muscle: trapezius
• Origin: medial third of the superior nuchal line, external occipital protuberance, ligamentum nuchae, spinous processes of vertebrae C7-T12
• Insertion: clavicle, medial side of the acromion and the upper crest of the scapular spine, tubercle of the scapular spine
• Action: elevates, depresses, rotates, and retracts the scapula
• Innervation: motor: spinal accessory (XI), proprioception: C3-C4
• Artery: transverse cervical a.

http://www.bartleby.com/107/illus385.html

Lateral cervical muscles

• Muscle: sternocleidomastoid (SCM)
• Origin: sternal head: anterior surface of manubrium; clavicular head: medial third of clavicle
• Insertion: mastoid process and lateral half of the superior nuchal line
• Action: draws mastoid process down toward the same side which causes the chin to turn up toward the opposite side; acting together, the muscles of the two sides flex the neck
• Innervation: spinal accessory nerve (XI) with sensory supply from C2 and C3
• Artery: submental and occipital arteries#13; 13;

http://musom.marshall.edu/ana/grosshom/allppt2002/Neck1%20Lectureff_files/frame.htm

Suprahyoid muscles

• Muscle: digastric
• Origin: anterior belly: digastric fossa of the mandible. Posterior belly: mastoid notch of the temporal bone
• Insertion: body of the hyoid bone
• Action: elevates hyoid bone, depresses mandible
• Innervation: ant. belly: mylohyoid nerve from the trigeminal nerve (V). post. belly: facial nerve (VII)
• Artery: submental and occipital arteries#13; 13;

http://musom.marshall.edu/ana/grosshom/allppt2002/Neck1%20Lectureff_files/frame.htm

Suprahyoid muscles

• Muscle: stylohyoid
• Origin: posterior side of the styloid process
• Insertion: body of hyoid bone
• Action: elevates and retracts hyoid bone
• Innervation: facial nerve (VII)
• Artery: ascending pharyngeal a.

http://musom.marshall.edu/ana/grosshom/allppt2002/Neck1%20Lectureff_files/frame.htm

Suprahyoid muscles

• Muscle: mylohyoid
• Origin: mylohyoid line of mandible
• Insertion: midline raphe and body of hyoid bone
• Action: elevates hyoid bone and tongue, depresses mandible
• Innervation: mylohyoid nerve from the inferior alveolar nerve, a branch of the trigeminal nerve (V)
• Artery: mylohyoid branch of the inferior alveolar a.#13; 13;

http://musom.marshall.edu/ana/grosshom/allppt2002/Neck1%20Lectureff_files/frame.htm

Suprahyoid muscles

• Muscle: geniohyoid
• Origin: mental spines of the mandible
• Insertion: body of hyoid bone
• Action: elevates hyoid bone, depresses mandible
• Innervation: ventral primary ramus of spinal nerve C1 via fibers carried by the hypoglossal nerve
• Artery: lingual a., submental a.

http://musom.marshall.edu/ana/grosshom/allppt2002/Neck1%20Lectureff_files/frame.htm

Infrahyoid muscles

• Muscle: sternohyoid
• Origin: post. surfaces of both the manubrium and sternal end of the clavicle
• Insertion: lower border of hyoid bone
• Action: depresses/stabilizes hyoid bone
• Innervation: ansa cervicalis
• Artery: superior thyroid a.
• Muscle: sternothyroid
• Origin: post. surface of the manubrium
• Insertion: thyroid cartilage
• Action: depresses/stabilizes hyoid bone
• Innervation: ansa cervicalis
• Artery: superior thyroid a.
• Muscle: thyrohyoid
• Origin: thyroid cartilage
• Insertion: lower border hyoid bone
• Action: elevates larynx, depresses/stabilizes hyoid bone
• Innervation: ansa cervicalis
• Artery: superior thyroid a.
• Muscle: omohyoid
• Origin: inferior belly: upper border of scapula; superior belly: intermediate tendon
• Insertion: inf. belly: intermediate tendon; sup. belly: lower border of hyoid bone
• Action: depress/stabilize hyoid bone
• Innervation: ansa cervicalis
• Artery: transverse cervical artery 13; ;

http://musom.marshall.edu/ana/grosshom/allppt2002/Neck1%20Lectureff_files/frame.htm

Anterior vertebral muscles

• Muscle: longus colli
• Origin: anterior tubercles and anterior surfaces of the bodies of C3-T3
• Insertion: ant. arch of atlas, ant. tubercles of C5-6, ant. surfaces of bodies of C2-4
• Action: flex, rotate, laterally bend neck
• Innervation: cervical and brachial plexus, C2-7
• Artery: deep cervical a.
• Muscle: longus capitis
• Origin: ant. tubercles of C3-6
• Insertion: basilar portion of occipital bone
• Action: flex head and neck Innervation: cervical plexus, spinal nerves C1-4
• Artery: deep cervical a.
• Muscle: rectus capitis anterior
• Origin: lateral mass of atlas
• Insertion: basilar portion of occipital bone
• Action: flexes the head Innervation: spinal nerve C1
• Artery: deep cervical a.
• Muscle: rectus capitis lateralis
• Origin: transverse process of atlas
• Insertion: occipital bone, anterolateral to foramen magnum
• Action: laterally tilts the head
• Innervation: spinal nerve C1 Artery: deep cervical a.
• Muscle: scalene, anterior
• Origin: ant. tubercles of transverse processes of C3-6
• Insertion: scalene tubercle of first rib
• Action: elevates first rib, flexes and laterally bends neck
• Innervation: brachial plexus, C5-C7
• Artery: ascending cervical a.
• Muscle: scalene, posterior
• Origin: post. tubercles of transverse processes of C2-C7
• Insertion: upper surface of the first rib behind the subclavian artery
• Action: elevates first rib, flexes and laterally bends the neck
• Innervation: brachial plexus, C3-C8
• Artery: ascending cervical a.
• Muscle: scalene, middle
• Origin: post. tubercles of the transverse processes of C5-C7
• Insertion: lateral surface of the second rib
• Action: elevates second rib, flexes and laterally bends the neck
• Innervation: brachial plexus, C7-C8
• Artery: ascending cervical a.

http://www.bartleby.com/107/illus387.html

Arteries of the neck

• Vessel: common carotid
• Source: brachiocephalic trunk, aortic arch
• Branches: external and internal carotid arteries
• Supplies: most of head and upper neck
• Notes: bifurcates at the level of the superior border of the thyroid cartilage; carotid body and sinus are located here
• Vessel: external carotid
• Source: common carotid a.
• Branches: superior thyroid, ascending pharyngeal, lingual, facial, occipital, post auricular, maxillary, superficial temporal arteries
• Supplies: upper neck, face, scalp 13; ;

http://musom.marshall.edu/ana/grosshom/allppt2002/Neck1%20Lectureff_files/frame.htm

Carotid sheath

Location/description: fascial investment that extends from the base of the skull to the root of the neck; contains the common carotid a., vagus nerve, and internal jugular vein

Carotid body and sinus

• CAROTID BODY:
• Description - small, reddish-brown ovoid mass that lies on the medial side of the carotid bifurcation
• Function – chemoreceptor that monitors the amount of oxygen in the blood CAROTID SINUS:
• Description – a slight dilation of the internal carotid artery
• Function – baroreceptor that reacts to changes in arterial pressure

http://calloso.med.mun.ca/~tscott/head/cbv.htm

Veins of the neck

• Vein: external jugular
• Tributaries: post. external jugular vein, transverse cervical, suprascapular, and ant. jugular veins
• Drains into: subclavian vein
• Regions drained: head, neck, shoulder
• Notes: contains valves that may not be fully functional

http://musom.marshall.edu/ana/grosshom/allppt2002/Neck1%20Lectureff_files/frame.htm

Veins of the neck

• Vein: posterior external jugular
• Tributaries: unnamed veins of the occipital region and superior neck
• Drains into: external jugular vein
• Regions drained: superficial portions of the post. head and neck

http://www.bartleby.com/107/illus563.html

• Vein: anterior jugular
• Tributaries: submental and communicating veins
• Drains into: external jugular vein
• Regions drained: superficial parts of the anterior neck
• Notes: valveless#13; 13;

• Vein: internal jugular
• Tributaries: pharyngeal, lingual, common facial, sternocleidomastoid, superior thyroid, and middle thyroid veins
• Drains into: brachiocephalic vein
• Regions drained: brain, cranial cavity, skull, face, viscera of the neck
• Notes: largest vein of the head and neck #13; 13;

http://www.bartleby.com/107/illus558.html

Vessels of the neck

• Subclavian vein
• Subclavian artery
• Internal jugular
• Internal jugular
• Common carotid artery

http://www.mythos.com/webmd/Content.aspx?P=ENDOCB

Lymph glands of the neck

http://www.bartleby.com/107/illus602.html

Lymph glands of the neck
	BLUE: Superficial Ring ; Submental, Submandibular, Parotid, anterior and external jugular nodes GREEN: Deep cervical chain - along Internal Jugular vein; receive lymph from all above nodes PURPLE: Jugular lymph trunk - to Right lymphatic duct or Thoracic duct

http://musom.marshall.edu/ana/grosshom/allppt2002/Neck1%20Lectureff_files/frame.htm

Lymphatic Drainage

Jugular Lymphatic Trunk Location: carotid sheath in root of neck Afferents from: deep cervical nodes Efferents to: the left thoracic duct, near its termination, and the right lymphatic duct Region drained: head and neck Notes: the jugular trunk carries the majority of the lymph from the head and neck Right Lymphatic Duct Location: root of neck on the right side Afferents from: formed by the union of the right jugular trunk, right subclavian trunk, and the right bronchomediastinal trunk Efferents to: the junction of the right subclavian vein and the right internal jugular vein Region drained: right half of head and neck, right upper limb, right side of chest 13; ;

http://www.bartleby.com/107/pages/page691.html

Lymphatic Drainage: Thoracic Duct
	Location: between the esophagus anteriorly and the thoracic vertebral bodies posteriorly Afferents from: formed by the union of the lumbar lymph trunks Efferents to: junction of the left subclavian vein and the left internal jugular vein Region drained: left side of neck Notes: largest lymphatic vessel #13; 13;

http://www.bartleby.com/107/pages/page691.html

The main function of the parathyroid glands is to produce parathyroid hormone, a regulator of calcium levels in the blood. PTH secretion is regulated by the amount of ionized calcium in plasma.

http://musom.marshall.edu/ana/grosshom/allppt2002/Neck1%20Lectureff_files/frame.htm

Venous Drainage

http://musom.marshall.edu/ana/grosshom/allppt2002/Neck1%20Lectureff_files/frame.htm

Salivary glands

http://musom.marshall.edu/ana/grosshom/allppt2002/Neck1%20Lectureff_files/frame.htm

http://musom.marshall.edu/ana/grosshom/allppt2002/Neck1%20Lectureff_files/frame.htm

Ansa Cervicalis
	Source: superior root (C1 and C2) and inferior root (C2 and C3) of the ansa cervicalis Branches: to infrahyoid muscles Motor: omohyoid, sternohyoid, sternothyroid, thyrohyoid, and geniohyoid muscles Sensory: none
http://www.geocities.com/medinotes/ansa_cervicalis_pic.htm

Basic Study Questions

  1.  Identify the major muscles of the neck.

  2.  What is the largest salivary gland?

  3.  What structures are contained in the carotid sheath?

Additional Study Questions