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What is the superficial/investing layer of dense CT (deep cervical fascia)? What muscles does it enclose?

A "sleeve" binding all structures in the neck. Splits twice to enclose the SCM & trapezius.


What does the infrahyoid fascia cover?

Covers supra- and infra-hyoid muscles (strap mm.)


What does the pretracheal fascia enclose?

Viscera including thyroid and parathryoid glands, larynx, trachea, esophagus.


What is enclosed in the carotid sheeth?

Carotid a., IJV, vagus n. (CN X)


What does the pre-vertebral fascia (deep cervical fascia) cover?

Covers vertebral musculature


What are the boundaries of the posterior triangle?

Anterior: SCM
Posterior: trapezius
Inferior: clavicle


What muscle divides the posterior triangle into the occipital triangle (superior) and omoclavicular triangle (inferior)?

Omohyoid muscle (inferior belly)


Sternocleidomastoid muscle: innervation and actions?

Innveration: accessory nerve (CN XI)
Unilateral actions: tilt head unilaterally, twist neck contralaterally.
Bilateral actions: extend the head, aid in respiration when head is fixed


Anterior scalene: OIIA?

Ori: anterior tubercles of transverse processes of C3-C6
Insertion: 1st rib
Innervation: ventral rami, C5, C6
Action: Elevates 1st rib, bends neck


Middle scalene: OIIA?

Ori: Posterior tubercles of transverse processes of C2-C7
Insertion: 1st rib
Innervation: ventral rami, C3-C8
Action: Elevates 1st rib, bends neck


Posterior scalene: OIIA?

Ori: posterior tubercles of transverse processes of C4-C6
Insertion: 2nd rib
Innervation: anterior rami of lower 4 cervical nerves C6-C8
Action: Elevates 2nd rib, bends neck


Where is Erb's point? What nerves emerge from it?

-Located 1/2 way along the posterior border of SCM
-Cutaneous (sensory) branches of the cervical plexus:
1. transverse cervical n.
2. great auricular n.
3. lesser occipital n.
4. supraclavicular n.
5. accessory n. (CN XI)


Transverse cervical n.: origin and action?

-Ventral rami of C2-C3
-Sensory to throat


Great auricular n.: origin and action?

-Ventral rami of C2-C3
-Sensory to bottom half of ear down neck


Lesser occipital n.: origin and action?

-Ventral rami of C2 (sometimes C3)
-Sensory to behind ear down to neck


Supraclavicular n.: origin and action?

-Ventral rami of C3-C4
-Has ant/middle/posterior branches. Sensory to area over clavicle.


Accessory n. (CN XI): origin and action?

-Medulla oblongata
-Motor to SCM and trapezius mm.


What are the roots of the phrenic nerve and what does it innervate?

-C3, C4, C5 (primarily C4!)
-Diaphragm (motor)


What's an important identifying landmark for the phrenic nerve?

It sits on top of the anterior scalene m.


What are the 2 roots of the ansa cervicalis? What nerves do they originate from?

Superior root (comes from C1) and inferior root (comes from C2 and C3)


What does the superior root of the ansa cirvicallis innervate?

Geniohyoid and thyrohyoid mm.


What does the inferior root of the ansa cirvicallis innervate?

Sternohyoid, sternothyroid, omohyoid mm.


Ventral rami of cervical plexus (C1-C4) innervates what mm.?

Rectus capitis lateralis, rectus capitis anterior, longus captitis, longis colli, levator scapulae, and scalene mm.


What 4 things are within the supraclavicular triangle (below the omohyoid)?

1. Lower portion of the brachial plexus (C6, C7, C8)
2. Subclavian a. and branches of the subclavian a. (VIT C + sometimes D)
3. Subclavian v.
4. Termination of the EJV


The ansa cervicalis lies on top of what structure?

External jugular vein


The phrenic nerve can be found on top of what structure?

Anterior scalene muscle


How many segments can the subclavian a. (near the anterior scalene) be broken into? What arteries/trunks do they contain?

-2 (sometimes 3). VIT C and sometimes D
1. Vertebral a.
1. Internal thoracic a.
1. Thyrocervical trunk
2. Costocervical trunk
3. Dorsal scapular a. (but often the suprascapular a. of the thyrocervical trunk is big enough to replace it)


What arteries are w/in the thyrocervical trunk?

-Suprascapular a. (army over)
-Inferior thyroid a.
-Transverse cervical a.
-Ascending cervical a.


What arteries are w/in the costocervical trunk? (teacher said "don't worry about it too much")

-Deep cervical a.
-Supreme intercostal a.


Anatomically, describe where the subclavian vein runs.

Behind the clavicle, in front of the anterior scalene