Anterior Triangle (Pre-Study) Flashcards
What muscle is contained in the superficial cervical fascia?
Platysma
What does the Platysma do?
Supports the tone of the neck and pulls the corners of the mouth down.
What innervates the platysma?
Facial N. (VII)
What layers is the deep fascia divided into?
- Investing layer
- Pervertebral Layer
- Pretracheal layer
- Carotid Sheaths
What does the investing layer of deep neck fascia surround?
all structures of the neck
What does the prevertebral layer of deep neck fascia surround?
vertebral column and deep muscles associated with the back
Muscles:
- Anterior, Middle, Posterior Scalene muscles
What does the pretracheal layer of deep neck fascia surround?
encloses viscera of the neck
What do the carotid sheaths of deep neck fascia surround?
surround:
- Common carotid
- internal cartotid
- internal jugular
- vagus nerve
Which layer of deep neck fascia recieves a contribution from the 3 other layers?
the carotid sheaths
What are the attachments of the investing fascia?
- Superior
- Laterally
- Inferiorly
Superior:
- External Occipital Protuberence
- Superior nuchal line
Laterally:
- mastoid process and zymgomatic arch
Inferiorly:
- Spine of the scapula
- acromion
- clavicle
- manubrium
What is the posterior, superior, and anterior attachment of the prevertebral layer?
Posterior:
Ligamentum Nuchae
Superior:
- Circular line at the base of the skull
Anterior:
- transverse processes CI to CVII
What does the pretracheal fasciae surround?
- Trachea
- Esophagus
- thyroid gland
What are the attachments of the pretracheal fascia?
- Superior
- Inferior
- Laterally
- Posteriorly
Superior:
Hyoid Bone
Inferior:
Upper thoracic cavity
Laterally:
Encloses the thyroid gland
Posteriorly:
Continous with fascia that surrounds the esophagus
What does the pretracheal fascia continue as posteriorly and what is the extent of this structure?
- Buccopharyngeal
What is contained in the third (visceral) compartment that is surrounded by the pretracheal layer?
- Pharynx
- Trachea
- Esophagus
- Thyroid Gland
What are the boundaries of the pretracheal space?
- anterior
- posterior
- between what two spaces
Anterior:
Back of the Infrahyoid muscles covered in the investing layer of cervical fascia
Posterior:
Front of the trachea covered with pretracheal fascia
*Between neck and anterior part of mediastinum
What are the boundaries of the retropharyngeal space?
Anterior:
Posterior surface of pharynx and esophagus covered in buccopharyngeal fascia
Posterior:
Cervical vertebrae covered in prevertebral fascia
What two veins unite to make the external jugular vein?
- posterior auricular
- Retromandibular
What muscle is the external jugular superficial to throughout its course?
sternocleidomastoid
Describe how the external jugular enters the subclavian vein at the lower part of the neck just superior to the clavicle.
- Immediately posterior to sternocleidomastoid the external jugular pierces the investing layer of cervical fascia
- It then passes deep to the clavicle to enter subclavian
Where do the anterior jugular veins come together?
Just superior to the hyoid bone
What is the cutaneous innervation to the posterior aspect of the neck?
- Dorsal Rami of Upper Cervical nn.
What supplies cutaneous innervation to the anteriolateral aspect of the neck (4 nerves)?
- Great Auricular
- Transverse Cervical
- Supraclavicular
- Lesser occipital
What makes up the borders of the anterior triangle?
- Laterally
- Superior
- inferior
Laterally:
- Anterior border of the Sternocleidomastoid
Superior:
- Inferior border of the Mandible
Inferior:
- apex that comes together at the midline of the neck
What makes up the borders of the posterior ∆?
- Anterior
- Posterior
- Inferior
Anterior:
- Posterior border of the Sternocleidomastoid
Posterior:
- Anterior border of trapezius
Inferior:
- Middle 1/3 of the clavicle
What 4 ∆s make up the anterior ∆?
- Submandibular ∆
- Submental ∆
- Muscular ∆
- Carotid ∆
What are the boundaries of the submandibular ∆?
Superior = Base:
- Inferior border of the mandible
Anterior Side:
- Anterior Belly of the Digastric
Posterior side:
- Posterior Belly of the Digastric
What are the boundaries of the Submental ∆?
Inferior = Base:
- Hyoid Bone
Anterior:
- Skin (maybe platysma?)
Posterior:
- Anterior Belly of the Digastric
What are the boundaries of the Muscular ∆?
Inferior Base:
- Sternocleidomastoid
Superior Apex:
- Hyoid Bone
Posterior side:
- Omohyoid
What are the boundaries of the Carotid ∆?
Base:
- Omohyoid Muscle
Superior Side:
- Posterior Belly of Digastric
Posterior:
- Sternocleidomastoid
What are the major contents of the Muscular ∆?
- Infrahyoid Muscles
- Thyroid Gland
What are the four infrahyoid muscles?
- Sternohyoid
- Omohyoid
- Sternothyroid
- thyrohyoid
What is the function of the infrahyoid muscles?
- To stabilize or depress the hyoid bone
T or F: the four infrahyoid muscles are in the posterior ∆
FALSE, they are in the anterior ∆
What muscles form the superficial layer of the infrahyoid muscles?
- SternoHYOID (medially)
- OmoHYOID (laterally)
What muscles form the deeper layer of infrahyoid muscles?
- SternoTHYROID (inferior to hyoid bone)
- THYROhyoid (superior to hyoid bone)
What 3 parts make up the thyroid gland?
L and R lobes
Isthmus
What are the major contents of the Carotid Triangle?
- Carotid Sheath
- Bifucation of Common Carotid a.
- Inital Distributions of the External Carotid a.
- Vagus nerve (CN X)
- Part of larynx
- Hypoglossal n. (CN XII)
Where does the common carotid artery bifurcate into its internal and external branches?
- Superior border of thyroid Cartilage
**Bifurcation happens inside the sheath
Which of the two carotid branches remains in the carotid sheath?
Internal Carotid
What is the first branch off of the external carotid?
- what is its path?
Superior Thyroid Artery
- Passes down and forward to reach the superior surface of the thyroid gland
What is the next artery up to arise from the anterior surface of the external carotid after the Superior Thyroid Artery?
*This is at the level of the Hyoid Bone
Lingual Artery
What nerve does the lingual artery pases deep to?
Hypoglossal n. (XII)
What artery arises just above the Lingual artery off of the external carotid a.?
Facial Artery
What artery arise posterior to the facial artery at the same level on the external carotid?
Occipital artery
What is the first branch off of the posterior aspect of the external carotid a.?
ascending pharyngeal a.
