Neck Flashcards
longus colli m.
flexes neck and contralaterally rotates it
innervated by C2-C6 ventral rami
anterior scalene muscle
elevates 1st rib when neck is fixed, flexes neck anteriorly, laterally, and rotates neck when the 1st rib is fixed; innervated by C4-C6 ventral rami
middle scalene muscle
elevates the 1st rib when the neck is flexed, flexes the neck anteriorly, laterally, and rotates the neck when 1st rib is fixed; muscle innervated by C3-C8
posterior scalene muscle
elevates 2nd rib when neck is fixed; flexes neck anteriorly, laterally, and rotates the neck when 2nd rib is fixed; muscle innervated by C6-C8 ventral rami
sternohyoid muscle
depresses the laryngeal apparatus when swallowing; muscle innervated by ansa cervicalis; inserts proximally on manubrium and clavicle, and distally on hyoid bone
sternothyroid muscle
depresses laryngeal apparatus when swallowing; muscle innervated by ansa cervicalis; inserts proximally at manubrium and distally to the thyroid cartilage
thyrohyoid muscle
depresses hyoid bone when the larynx is fixed or elevates larynx when the hyoid bone is fixed; innervated by C1 branch that traveled with hypoglossal (CN XII)
omohyoid muscle
depresses hyoid bone relative to fixed scapula;
muscle innervated by ansa cervicalis;
inserts proximally to upper border of scapula and distally to hyoid bone (curves)
Subclavian artery
on right side: brachiocephalic artery
on left side:
aorta
Branches into: Vertebral artery Thyrocervical trunk Internal thoracic artery Costocervical artery
Vertebral artery
1st branch off subclavian artery; ascends between anterior scalene and longus colli m. and eventually courses through transverse foramen of C6-C1–> foramen magnum–>supplies posterior region of brain
Thyrocervical trunk
2nd branch off subclavian artery; branches further into:
- inferior thyroid artery
- ascending cervical artery
- transverse cervical artery
- suprascapular artery
Inferior thyroid artery
supplies inferior poles of thyroid gland
Ascending cervical artery
supplies the longus coli muscle, cervical vertebra bodies, and cervical spinal cord
Transverse cervical artery
will bifurcate into the superficial branch (which supplies traps) and a deep branch ( supply levator scapulae and rhomboid muscles)
Internal thoracic artery
branches inferiorly from subclavian artery–>courses inferiorly along lateral edge of sternum–>gives rise to the anterior intercostal arteries, superior epigastric, and musculophrenic arteries.
Costocervical trunk
branches from the subclavian artery; courses posteriorly over the dome of pleural cavity & branches into deep cervical artery and superior intercostal artery
Nerves of neck
Vagus nerve- which innervates thoracic viscera
Recurrent laryngeal nerve- innervates intrinsic laryngeal muscles; on right side it comes off of vagus nerve and wraps underneath subclavian artery; on left side it comes off vagus nerve and wraps underneath aorta arch
Phrenic nerve- innervates the diaphragm
Cervical sympathetic trunk- note there are no white rami communicans in cervical region
Anterior Triangle Contents
Submandibular triangle, submental triangle, muscular triangle, carotid triangle
Submandibular triangle
contains submandibular gland, submandibular lymph nodes, hypoglossal nerve, nerve to mylohyoid, facial artery, facial vein
Submental triangle
contains submental lymph nodes, tributaries of the anterior jugular vein, and geniohyoid muscle
Muscular triangle
contains sternohyoid, sternothyroid, thyrohyoid, and omohyoid muscles, thyroid gland, and parathyroid gland
Carotid triangle
contains common carotid, internal carotid, external carotid arteries, internal jugular vein, vagus nerve, accessory nerve, hypoglossal nerve, ansa cervicalis, and transverse cervical nerve, and cervical branch of facial nerve
Posterior triangle contents
occipital triangle and omoclavicular (subclavian) triangle
Occipital triangle
contains splenius capitis, levator scapulae, middle scalene, posterior scalene, accessory nerve, supraclavicular nerves,branches of cervical plexus, trunk of brachial plexus, transverse cervical artery, and transverse cervical vein and cervical lymph nodes
Omoclavicular (subclavian) triangle
contains subclavian artery, subclavian vein, suprascapular artery, suprascapular vein, and brachial plexus
sternocleidomastoid muscle
attaches superiorly to mastoid process (bony structure behind ear), and inferiorly to the manubrium and clavicle
innervated by CN 11 (accessory nerve)
rotates head to opposite side, flexes head, raises thorax
stylohyoid muscle
attaches proximally to styloid process (anterior to mastoid process) and distally to hyoid bone
innervated by branch of CN 7 (facial nerve)
elevates hyoid bone & base of tongue, retracts hyoid bone
mylohyoid muscle
muscle attaches to the mandible on each side of the mylohyoid line; forms the floor of oral cavity
innervated by nerve to mylohyoid (branch of inferior alveolar nerve of CN V3)
elevates hyoid bone and tongue when speaking and swallowing; depresses mandible
Geniohyoid muscle
deep within submental triangle; muscle attaches to mental process on inside of mandible and to hyoid bone
innervated by cervical nerve C1 that travels with CN 12 (hypoglossal n)
protracts hyoid bone
Common carotid artery
Right common carotid branches off brachiocephalic while left common carotid branches off aortic arch.
Will branch into internal and external carotid arteries near hyoid bone
Internal carotid artery
doesn’t give off any branches but contains the carotid sinus (which has baroreceptors that monitor BP) and the carotid body (which has chemoreceptor that monitors partial pressure of O2)
External carotid artery
gives off branches below:
- Superior thyroid artery - Ascending pharyngeal artery - Lingual artery - Facial artery - Occipital artery
Superior thyroid artery
supplies the thyroid and parathyroid glands; also gives off the superior laryngeal artery
superior laryngeal artery
pierces the thyrohyoid membrane to supply the mucosa of the supraglottic cavity
ascending pharyngeal artery
ascends vertically to supply the pharynx, soft palate, palatine tonsillar bed, and auditory tube
lingual artery
courses through the carotid triangle and joins the sublingual artery deep to the hyoglossus muscle to supply the tongue and sublingual gland
facial artery
courses deep to submandibular gland and then around the body of the mandible to enter the superficial face anterior to the masseter muscle
occipital artery
courses deep to posterior belly of digastric m. en route to occipital region, where it supplies sternocleidomastoid m., deep neck muscles, and meninges of posterior cranial fossa.
posterior auricular artery
supplies parotid gland, lateral facial muscles and ear
Cervical plexus (C1-C4)
contains:
- lesser occipital nerve (C2)-innervates scalp posterior and superior to the ears
- great auricular nerve (C2-C3)- innervates skin over the parotid gland, angle of jaw, and posterior ear
- transverse cervical nerve (C2-C3)- innervates skin over anterior triangle of neck
- supraclavicular nerve (C3-C4)- innervates skin over the clavicle and superior region of thorax
