Cartilages
What is the only cartilage that forms a complete ring around the airway and why?
The cricoid cartilage
Other tracheal rings have open posterior aspects to allow flexibility while swallowing
This ligament connects the two anterior cartilages of the larynx
Median cricothyroid ligament
The cricothyroid does what?
Stretches vocal ligament/tenses cords
What is the only intrinsic laryngeal muscle not motor innervated by the recurrent laryngeal nerve?
The cricothyroid
What is the opening between the vocal folds called?
Rima glottidis
Three parts/segments of the arytenoid cartilage
Vocal process - attaches to vocal ligaments
Muscular process - Muscle attachment point
Apex - where corniculate cartilage sits
This membrane anchors the larynx to the major bony structure of the anterior neck
Thyrohyoid membrane, connecting the thyroid cartilage to the hyoid bone
The posterior cricoarytenoid does what?
Rotates the vocal processes of the arytenoids laterally
Opens/ABducts vocal cords
What is the origin of the internal laryngeal nerve, and what does it innervate?
Superior laryngeal n./CNX
Sensory innervation to laryngeal mucosa above the level of the vocal cords
What is the difference between the vestibule and the ventricle?
The vestibule is from the inlet to the vestibular folds (false cords)
The ventricle is the area between vestibular folds and vocal folds (true cords)
Name all six cartilage structures involved in the larynx
Paired: Cuneiforms, corniculate, and arytenoid cartilage
These two structures make up the conus elasticus
Vocal ligament
Lateral cricothyroid ligament/cricovocal ligament
The lateral cricoarytenoid does what?
Rotates vocal processes of the arytenoids medially
Closes/ADducts vocal cords
What is the origin of the external laryngeal nerve, and what does it innervate?
Superior laryngeal n./CNX
Motor innervation to cricothyroid and inferior constrictors
What arteries supply the larynx and where do they branch from?
Superior laryngeal artery (branch of superior thyroid artery, which branches from the external carotid)
Inferior laryngeal artery (branch of inferior thyroid artery, branch of thyrocervical trunk)
These two cartilage structures form a joint
the inferior horn of the thyroid cartilage and the lamina of the cricoid cartilage
The opening on either side of the thyrohyoid membrane grants passage to which two structures?
Internal laryngeal n. and superior thyroid vessels -> superior laryngeal vessels
What do the transverse and oblique arytenoid muscles do?
Slide the arytenoids medially (ADduction)
Closes posterior rima glottidis
What is the origin of the recurrent laryngeal nerve and what does it innervate?
Vagus n.
Motor to all muscles of larynx except cricothyroid
Sensory to mucous membranes below vocal cords
Which three cartilages are visible/appreciable when the larynx is covered by connective tissue?
Epiglottic
Corniculate
Cuneiform
become "tubercles" when covered
This cartilage is adherent to the cuneiform ligament
the cuneiform cartilage (paired)
These ligaments (2) and membrane (1) make up the laryngeal vestibule and vestibular folds
Aryepiglottic ligament - forms aryepiglottic fold
Quadrangular membrane - forms walls of vestibule
Vestibular ligament - inferior part of quadrangular membrane, becomes vestibular fold
What does the thyro-arytenoid do and how is it related to the vocalis muscle?
Pulls the arytenoids anteriorly, relaxing the vocal cords
The vocalis muscles line the medial aspect of the thyroarytenoids, and their vibration when close together is what creates speech (the tightening or loosening of the cords changes the pitch)
What are the pathways of the right and left recurrent laryngeal nerves/where do they branch off of the vagus n.?
Left: Branches off the vagus anterior to the aortic arch and loops posterior behind the ligamentum arteriosum (remnant of PDA) to ascend
Both: ascend between trachea and esophagus
What are the five levels/segments of the larynx from superior to inferior?
Epiglottis
Supraglottis
Vocal cord
Glottis/glottic opening
Subglottic/infraglottic area