Week Six Flashcards
Larynx: Extrinsic Parts & Endoscopy (74 cards)
How is the larynx positioned?
Suspended between the skull above and the bones of the torso below
What are the key connection points on the skull?
Styloid processes
Mastoid processes
What are the styloid processes?
Stylus shaped projections from the base of the skull, serving as the origin for several muscles
Located on the inner side of the jaw
What are the mastoid processes?
Larger, smoother protrusions behind the earlobes, providing insertion points for muscles
What is the hyoid bone?
Horseshoe-shaped bone that does not directly contact other bones
Suspended by a network of ligaments and muscles
What does the hyoid bone provide essential support for?
Only solid part of the tongue, offering critical structural support
Serves as an anchor for the larynx, facilitating speech and swallowing
What are the 3 projections of the hyoid bone?
Greater horn
Lesser horn
Body
What function does the sternum have for larynx suspension?
Manubrium acts as an anchor point for multiple muscles
What are the four extrinsic laryngeal muscle groups?
Pharyngeal constrictors
Infrahyoids
Suprahyoids
Pharyngeal elevators
What are pharyngeal constrictors?
Muscles that form the beck and side walls of the pharynx
Key for laryngeal support
What are the 3 types of pharyngeal constrictors?
Inferior pharyngeal constrictor (lowest)
Middle pharyngeal constrictor
Superior pharyngeal constrictor (highest)
Where does the inferior pharyngeal constrictor originate?
Originates are the sides of the cricoid and thyroid cartilages
Where does the inferior pharyngeal constrictor insert?
Inserts into the median raphe of the pharynx
What is the function of the inferior pharyngeal constrictor?
Pulls the larynx backward and upward (diagonally) when contracted and narrows the laryngopharynx (lower part of the pharynx
Where does the middle pharyngeal constrictor originate?
Originates from the greater and lesser horns of the hyoid bone and stylohyoid ligament
Where does the middle pharyngeal constrictor insert?
Inserts into the median raphe of the pharynx
What is the function of the middle pharyngeal constrictor?
Retracts and elevates the hyoid bone, narrowing the oropharynx
Useful for ejectives
What are the infrahyoid muscles?
Strap muscles
Crucial for forced inspiration and phonation
Connect to the hyoid bone from beneath
Innervated from C1-C3
What are the 4 main strap muscles?
Sternohyoid
Sternothyroid
Thyrohyoid
Omohyoid
Where does the sternohyoid muscle originate?
Manubrium of the sternum
Where does the sternohyoid muscle insert?
Hyoid bone
What is the function of the sternohyoid muscle?
Contraction will lower the hyoid bone, linking the sternum to the hyoid
Where does the thyrohyoid muscle originate?
Thyroid cartilage
Where does the thryohyoid muscle insert?
Hyoid bone