Triangles of Neck/ Larynx

Question 1

Anterior Triangle Boundaries

Answer 1

midline of neck, SCM, lower mandible

Question 2

Posterior Triangle Boundaries

Answer 2

SCM, trapezius and clavicle

Floor: splenius capitis, semispinalis capitis, levator scapulae, scalenes

Question 3

Carotid sinus vs carotid body

Answer 3

Sinus in ICA->baroreceptor (increased BP)

Body at bifurcation–> chemoreceptor O (oxygen)

Question 4

Anterior Triangle Arteries

Answer 4

Common carotid bifurcates @ C3-C4 into ICA and ECA

Question 5

ECA branches

Answer 5

Superior thyroid A
          Superior 
              laryngeal A
Ascending pharyngeal 
   A b/t bifurcation 
    (medial pharynx)
Lingual A
Facial A
Occipital A (bone)
Posterior Auricular A 
Maxillary A
Superficial temporal A

Question 6

Anterior Triangle muscles

Answer 6

Suprahyoid: elevate hyoid and larynx in phonation and swallowing, form floor of oral cavity and stabilize tongue and hyoid

Infrahyoid: depress hyoid and larynx

Question 7

Suprahyoid Ms

Answer 7

Mylohyoid
Stylohyoid (straddles posterior digastric)

Digastric
Geniohyoid (oral cavity)

Question 8

Infrahyoid Ms

Answer 8

Sternohyoid
Omohyoid
Sternothyroid
Thyrohyoid

Question 9

Posterior Triangle Arteries

Answer 9

Transverse cervical A
  lateral and superficial to 
   anterior scalene and 
   phrenic N
Suprascapular A
  inferior and lateral "

both off of thyrocervical trunk

Question 10

Posterior Triangle Veins

Answer 10

External jugular vein: union of posterior auricular and retromandibular veins
anterior to SCM
drains into subclavian

Subclavian Vein
anterior to anterior
scalene, joins IJV–>
Brachiocephalic vein

Question 11

What does it mean if you can see EJV externally

Answer 11

heart failure, superior vena cava obstruction

Question 12

Where do you place central lines?

Answer 12

Subclavian vein (R mostly b/c more straight)

Poke too deep, you can hit subclavian A or lung–> pneumothorax

Question 13

Posterior Triangle Nerves

Answer 13

cutaneous, CN XI, brachial plexus roots/trunks, phrenic N

Question 14

Erb’s point

Answer 14

middle of posterior SCM
Cutaneous branches of cervical plexus:

Lesser occipital
Greater auricular
Transverse cervical
Supraclavicular

Question 15

Lesser Occipital N

Answer 15

C2, skin of neck and scalp posterior to ear

Question 16

Great auricular N

Answer 16

C2-C3, skin and sheath over parotid gland, mastoid process, ear and angle of mandible

Question 17

Transverse Cervical N

Answer 17

C2-C3, skin of anterior cervical region

Question 18

Supraclavicular N

Answer 18

C3-C4, skin over clavicle and shoulder

Question 19

Spinal accessory (CN XI)

Answer 19

Exits skull via jugular foramen to anterior triangle–>deep to SCM (innervates it) –> posterior triangle–> (where susceptible to accidental cutting) trapezius

most common accidentally cut nerve

torticollis if damaged–> head moves toward damage, face away

Question 20

Phrenic N

Answer 20

C3, C4, C5 keep the diaphragm alive

anterior to anterior scalene, immediately posterior to carotid sheath

Question 21

Submandibular contents

Answer 21

both bellies of digastric, interior mandible

submandibular gland and lymph nodes, CN XII, N to mylohyoid, parts of facial A and V along mandible

Question 22

Submental contents

Answer 22

midline of neck, anterior digastric x2, body of hyoid

submental lymph nodes
small veins that make
anterior jugular V

Question 23

Muscular contents

Answer 23

body of hyoid, midline of neck, superior belly of omohyoid, SCM

sternohyoid
sternothyroid
thyrohyoid
thyroid and parathyroid 
    glands, larynx, 
    trachea, esophagus
common carotid A, 
    superior thyroid A, 
    inferior thyroid A
anterior jugular V, 
    thyroid veins
ansa cervicalis, external 
    laryngeal N, recurrent 
    laryngeal N

Question 24

Carotid contents

Answer 24

posterior belly of digastric, superior belly of omohyoid, SCM

branches of ECA
internal and external 
  laryngeal nerves, CN 
  XII, CN XI, ansa 
  cervicalis
carotid sheath

Question 25

Carotid Sheath

Answer 25

Ansa cervicalis anterior or embedded in sheath Common carotid A anterior medial Internal jugular vein anterior lateral Vagus nerve posterior

Question 26

Vagus nerve branches

Answer 26

Pharyngeal branch ``` Superior laryngeal N internal branch of " sensory above vocal cord, pierces thyrohyoid membrane with superior laryngeal A external branch of " innervates cricothyroid ``` Carotid body branch ``` Recurrent laryngeal N Inferior laryngeal N All intrinsic laryngeal muscles with sensory below vocal cord ```

Question 27

Occipital triangle contents

Answer 27

Part of EJV Posterior branches of cervical plexus CN XI Trunks of brachial plexus Cervical lymph nodes

Question 28

Subclavian triangle contents

Answer 28

dorsal scapular A (via subclavian A) part of subclavian V suprascapular A and lymph nodes

Question 29

Superficial Fascia

Answer 29

Between dermis and investing layer of deep fascia contain SubQ tissue, cutaneous nerves, blood, lymph, fat and PLATYSMA

Question 30

Deep Fascia

Answer 30

Investing layer Pretracheal Prevertebral Carotid Sheath

Question 31

Investing layer of deep fascia

Answer 31

most superficial of deep fasica surrounds entire neck, encloses SCM, trap and glands (parotid and submandibular) attaches to manubrium, clavicals, scapula, occipital, temporal, zyg arch, mandible, hyoid and vertebrae -->mumps d/t expanding parotid glands held by this tight fascia

Question 32

Pretracheal layer of deep fascia

Answer 32

only in anterior neck, blends with pericardium makes up muscular layer over infrahyoid muscles, buccopharyngeal fascia and a visceral layer

Question 33

Prevertebral layer of deep fascia

Answer 33

encloses vertebral column and muscles, extends laterally into axillary sheath of arm base of head to mediastinum

Question 34

Carotid Sheath (fascia wise)

Answer 34

blends with prevertebral and pretracheal fascia common carotid A anterior and medial internal jugular vein anterior and lateral vagus nerve most posterior

Question 35

Retropharyngeal Space

Answer 35

it is posterior to pharynx buccopharyngeal fascia (pretracheal) anterior prevertebral fascia posterior carotid sheaths lateral -->abscess causes swelling, makes difficult swallowing or breathing

Question 36

Venous drainage of neck and head

Answer 36

EJV formed via posterior auricular and retromandibular veins Anterior to SCM Drains external face--> Subclavian V ``` IJV begins in cranial cavity as continuation of sigmoid sinus exits via jugular foramen in carotid sheath combines with subclavian V to form brachiocephalic vein has inferior bulb to stop backflow of blood ``` AJV paired veins in anterior neck drains this area to subclavian V ``` Dural venous sinuses drain blood in head superior and inferior sagittal sinuses meet in confluence of sinus--> transverse sinus--> sigmoid sinus-->IJV ```