Anatomy of the Larynx
What structures form the thyroid cartilage?
2 lamina plates fused at the midline (oblique line)
What is on top of the cricoid and what does it attach?
A facet that attaches the arytenoid cartilages.
Name the paired cartilages of the larynx
Arytenoids, corniculate, cuneiform
What is the purpose of the epiglottis?
Closes off your airways when you are swallowing and drinking.
What does the inferior cornu of the thyroid articulate with?
Cricoid cartilage
Name the 3 unpaired cartilages in the larynx
Epiglottis, thyroid, cricoid
Name the 2 main types of laryngeal membranes and describe them
Extrinsic: provides attachment between the hyoid bone and the laryngeal cartilages OR the trachea and the laryngeal cartilages. Intrinsic: connects cartilages of the larynx to each other. Forms the support structure for the cavity of the larynx as well as the vocal folds.
What does the superior cornu of the thyroid articulate with?
Hyoid bone
What are the aryepiglottic folds and what is their purpose?
It is one of the membranes of the larynx and it houses the cuneiform cartilage.
What is the corniculate cartilage?
It's the extension of the arytenoid apex.
What is the function of the hyoepiglottic ligament?
It's there to hold the epiglottis up so it doesn't always flop down.
Name the 2 processes of the arytenoids, their relative positionings, and what they do.
Muscular process: More lateral. Point of attachment for 4 muscles of the larynx. These are the muscles that abduct and adduct your vocal folds. Vocal process: More medial. Point of attachment of the vocal folds.
Describe the positioning and shape of the arytenoids
Small, pyramid shaped cartilages positioned on top of the cricoid cartilage
What is the secondary purpose of the larynx?
Speech production
What are the dimensions of the epiglottis relative to other laryngeal structures and what is its overall shape?
Starts just above the thyroid notch and goes upward into the hyoid bone, extending slightly above it. It Sits at the base of the tongue and is a leaf-like structure made of ELASTIC cartilage.
What is the position of the cricoid cartilage relative to all other cartilages of the larynx? What is its overall shape?
The cricoid cartilage is the most inferior of all other laryngeal cartilages. It sits directly on top of the trachea and has a ring-like structure.
Describe in more detail the shape of the cricoid cartilage.
The cricoid is higher in the BACK than in the front. This creates a gap that allows the vocal chords to pass through it. It is also thinner in the front and gets thicker towards the back.
What is the cricothyroid joint, where is it located, and what does it do?
The cricothyroid joint is a hole on the laminas of the cricoid cartilage. This is where the inferior cornu of the thyroid fixes and allows the thyroid to rock back and forth.
What is the epiglottis joined with and by what?
The epiglottis is joined with the artytenoid cartilages by the aryepiglottis folds.
What are the points of attachments for cartilage and ligaments on the hyoid bone?
The greater and lesser cornu
What is unique about the hyoid bone vis-a-vis all other bones in the human body?
The hyoid bone does not attach to any other bone
What are the dimensions of the larynx?
The larynx extends form the hyoid bone to the cricoid cartilage. Inside the larynx is where the vocal chords are housed.
What structure exists at the 2 lamina plates of the thyroid cartilage and what does it attach?
The oblique line. Attaches muscles only.
Where is the hyoid bone located in terms of relative position to vertebra and what is its general shape?
The third vertebra; horseshoe shaped.
What laryngeal structure attaches to the greater cornu of the hyoid bone?
The thyroid
What is the function of the lateral/median glossoepiglottic ligaments?
There is a mucous membrane that surrounds these ligaments. This membrane forms little valleys on either side called valleculae, which direct food and liquids into the esophagus.
Describe the cuneiform cartilage and its function
This cartilage is embedded within the aryepiglottic fold. It provides the support for the aryepiglottic fold.
Name all of the extrinsic membranes (and associated ligaments) of the larynx and what they attach
Thyrohyoid membrane: connects the hyoid to the thyroid. Also stretches across the space between the greater cornus of the hyoid bone. Lateral thyrohyoid ligament: posterior to the thyrohyoid membrane. Runs from the superior cornu of the thyroid to the posterior tip of the greater cornu of the hyoid. Median thyrohyoid ligament: runs from the corpus of the hyoid to the upper border of the anterior part of the thyroid. Hyoepioglottic ligament: attaches epiglottis to the corpus of the hyoid Lateral/median glossoepiglottic ligaments: attaches epiglottis to the tongue in the lateral regions. Cricotracheal membrane: connects the cricoid and trachea Thyroepiglottic ligament: Connects the inner side of the thryoid to the epiglottis.
What is the most superior structure on the thyroid?
Thyroid notch
What is the primary purpose of the larynx?
To keep food and liquids from going down the airway and to expel foreign matter.
What is the hyoid bone's overall purpose?
To support the exterior of the larynx