Anterior Triangle Flashcards
overall, all of the neck is in the?
superficial cervical fascia
what are the boundaries of anterior triangle?
superior= inferior border of the mandible lateral= anterior border of SCM inferior= suprasternal notch
what is special about the digastirc muscle?
it has a fascical sling that attaches to the hyoid bone that creates a pulley at a 90 degree angle; where posterior and anterior belly’s are divided
name the 4 subtriangles of the anterior triangle?
- submental (1) -middle under chin
- submandibular (2) -sides under chin
- carotid (2) -gland area
- muscular (2) -throat
what is the only unpaired sub-triangle?
submental
submental triangles houses?
submental lymph nodes and anterior jugular veins that drain lymph
submental triangle bounded by?
anterior bellies of digastric and the hyoid bone
*floor is mylohyoid muscle
Submandibular triangle bounded by?
by the anterior and posterior belly of digastric and the mandible
*Floor is both the mylohyoid and hyoglossus
Submandibular triangle contents
- two nerves (nerve to mylohyoid and hypoglossal nerve)
* three arteries and three veins: lingual, submental, and facial
Facial artery branches off of? BS to?
Branches off external carotid; loops over the mandible and carries blood to the face
Submental artery is a branch off? BS to?
Branch off facial artery; courses toward mental region
Lingual artery is a branch off? Goes where?
Branch off external carotid; dives deep to the hyoglossus muscle and runs up toward the oral cavity
Hypoglossal nerve (CN XII) gets to submandibular triangle how?
Loops around to innervate intrinsic tongue muscles; loops under andwithin the submandibular triangle toget to the tongue
muscular triangle bounded by?
midline of neck, hyoid, superior belly of omohyoid, and anterior border of SCM
muscular triangle houses?
infrahyoid muscles thyroid gland parathyroid glands lyrngeal cartilage (thyroid and cricothyroid) ansa cervicalis
two types of lyrengeal cartilage?
thyroid and cricothyroid
muscular triangle muscles?
sternohyoid omohyoid thyrohyoid sternothryoid cricothyroid
strap muscles =
infrahyoid muscles
cricothyroid muscle functions for? Found in?
does not function in the neck, functions in the larynx
*found in muscular triangle
muscular triangle innervation?
SO2S are innervated by the ansa cervicalis
carotid triangle bounded by?
mandible, strap muscles, and SCM
carotid triangle houses?
*shit ton of important things
internal caratid artery (ICA) has how many branches in neck?
none. No branches until it gets to brain at circle of Wilis
external caratid artery (ECA) is located where? branches?
located on top of investing layer
*lingual and facial branches (and more)
the common caratid artery splits into?
external and internal caratid artery
What does the common facial vein drain? what does it drain INTO?
drains and face and viscera
*drains into internal jugular vein and then the IJV continues down to meet subclavian vein (and the IJV and subclavian forms brachiocephalic vein)
what forms brachiocephalic vein?
internal jugular vein ( IJV) and subclavian
All the vessels found in carotid triangle?
ICA IJV common facial vein ECA (with branches) common carotid
All the nerves found in carotid triangle?
sympathetic trunk vagus ansa cervicalis hypoglossal carotid sinus nerve
sympathetic trunk (nerves) continues through the _____ triangle toward the head?
carotid triangle towards head
What triangle is the vagus nerve and ansa cervicalis found?
carotid
what is ansa cervicalis?
the motor branches off the cervical plexus made of superior and inferior root; formed by C1, C2, C3
the hypoglossal nerve courses through the ____ triangle before it enters the ____ triangle?
courses through the carotid triangle before it enters the submandibular triangle
Carotid sinus nerve is a branch off of what?
branches off CN IX (glossopharyngeal)
Baroreceptor
regulates blood pressure
Chemoreceptor
regulates oxygen levels
Carotid sinus
swelling at the most proximal part of the internal carotid; swelling has baroreceptors within it that sense blood pressure and sends feedback to help regulate BP
Carotid body
tissue that contains chemoreceptors that sense oxygen/CO2 blood gas levels
what does the Carotid sinus nerve do?
carries information (feedback) from carotid body and carotid sinus concerning blood pressure and oxygen levels back to the CN9 (glossopharyngeal), therefore to brain
cervical plexus is what vertebra?
C1-C5
Each of the emerging Ventral rami split into 2 bundles
top bundle meshes with cervical nerve
above it and the bottom bundle meshes with the cervical nerve below it
*each of the loops have dorsally projecting (posteriorly projecting) sensory branches and anteriorly (Ventral) projecting motor branches
HOW TO REMEMBER IF efferent AND afferent or ventral/anterior AND dorsal/posterior are either sensory or motor?!?!?!
Emmett= efferent and Victor= ventral/anterior
- *emmett and victor are both physical aka MOTOR
- *Ass is Posterior for pleasure/sensory
what does the carotid sheath surround?
common carotid artery, internal jugular vein (IJV) and vagus nerve
carotid sheath is comprised of what cervical fascia?
All 3 layers of deep cervical fascia; they all come together to form sheath (investing, pretracheal, prevertebral)
where is the ansa cervicalis in relation to carotid sheath?
Ansa cervicalis sits on top of the carotid sheath
All of the drainage from head and neck follow?
the same chain of jugular nodes down to the venous angle
*mandibular incisors to submental nodes go back in the neck to follow this pattern
what is venous angle?
Junction of subclavian vein with internal jugular vein, it is the junction where they form brachiocephalic. *important because it is where lymph dumps into venous return to heart
pretracheal layer of deep cervical
fascia is located?
Below/deep to investing layer and is LIMITED TO ANTERIOR NECK
pretracheal layer of deep cervical
fascia consists 2 parts. Name them
1) a thin muscular part which encloses the
infrahyoid muscles (and forms pulleys),
2) visceral part, which encloses the thyroid gland, trachea, and esophagus
pretracheal layer of deep cervical
fascia is continuous with ________ fascia?
buccopharyngeal
describe buccopharyngeal fascia
between back part of thyroid gland separating the viscera from the vertebral column
- extension of pretracheal layer
- ** separates a POTENTIAL SPACE (Retropharyngeal Space) for infection to spread
what is Retropharyngeal Space?
a POTENTIAL SPACE for infection to spread created by buccopharyngeal fascia
Retropharyngeal Space location? boundaries?
behind pharynx
- It extends superiorly to the base of the skull and inferiorly to the mediastinum
- is a secondary space (2°)!!!
- is bound by the buccopharyngeal fascia anteriorly, the prevertebral fascia posteriorly, and the carotid sheaths laterally
Retropharyngeal Space is dangerous because?
alllows for spread of infection
- *carries dental infections (or from tonsils or middle ear) from the oral cavity down to the mediastinum;
- any kind of infection that spreads in this space can spread all the way down to the mediastinum = can have sepsis, pericarditis
define mediastinum
a membranous partition between two body cavities or two parts of an organ, especially that between the lungs
