The Phonatory System Flashcards
What is the larynx made of?
Cartilage and muscle
The larynx is a variable valve, this means what?
Laryngeal resistance may vary from minimal to absolute
What sex is the larynx more prominent in?
Men
What is the thyroid notch?
A V-shaped notch on top of the larynx which indicates where the VFs attach anteriorly
Where approximately is the larynx located?
Around the level of the 3rd to 6th cervical vertebrae
What attaches anteriorly to the thyroid notch?
Vocal folds
The vocal folds are used for ________
Voicing
Hyoid bone
The only bone in the body that does not articulate with another. The larynx is suspended interiorly from it by extrinsic laryngeal muscles and ligaments
What are the protective functions of the laryngeal valve mechanism?
Prevents air from escaping the lungs, prevents foreign substances from entering the larynx, expels foreign substances from the larynx by making us couch
Vocal folds are loosely _________ and air from the lungs does what?
Adducted, air blows them open briefly
After being blown open by air from the lungs, what happens to the vocal folds?
Their elastic nature and the reduction in subvocal air pressure slings them back into their original abducted position
How many cycles/second (Hz) do mens VF vibrate? Womens?
Men - 125 Hz, women - 210 Hz
Why do men’s VF vibrate more slowly than women’s?
The hyoid bone is part of the ______ skeleton
Axial
What is the largest part of the hyoid bone?
The corpus, or body
The hyoid provides an anterior attachment for most of the ________ muscle.
Tongue
What muscles is the hyoid suspended by?
They are called the hyoid sling muscles: stylohyoid, digastricus (posterior and anterior), geniohyoid, sternohyoid, sternothyroid, omohyoid
Which muscles are known as the strap muscles of the neck?
Geniohyoid, thyrohyoid, sternohyoid, sternothyroid, omohyoid
What are the nine cartilages that make up the larynx?
Thyroid, cricoid, epiglottis, 2 arytenoid, 2 corniculate, 2 cuneiform
What type of cartilage is thyroid?
Hyaline
What type of cartilage is cricoid?
Hyaline
What type of cartilage is epiglottis?
Elastic
What type of cartilage are the arytenoids?
Hyaline
What type of cartilage is corniculate cartilage?
Elastic
What type of cartilage is cuneiform?
Elastic
What is the largest laryngeal cartilage?
Thyroid
What is the thyroid cartilage made of?
Two hyaline plates called the thyroid laminae (which are fused together)
The thyroid cartilage has ____ ______.
Four cornua (horns), 2 are superior and 2 are inferior
The cricoid cartilage sits on top of the _______
Trachea
The cricoid cartilage is attached by the ____________ ________
Cricotracheal ligament
The cricoid cartilage consists of what two parts?
Anterior arch and posterior quadrate laminae
Along the sides of the cricoid cartilage are _________ ______ that provide __________ _______ for the _________ _____ of the _________ cartilage.
Aong the sides of the cricoid cartilage are articular facets that provide attachments for the inferior horns of the thyroid cartilage.
The attachment of the inferior horns to the thyroid cartilage produces a _____________ _____ _____, which enables the cricoid and thyroid cartilages to pivot
Diarthrodial pivot joint
Why do men’s VF vibrate slower than women’s?
They are longer, with more mass, and less tension
What paired cartilages sit on top of the posterior sloping border of the cricoid cartilage?
Arytenoid cartilages
What are the two aretynoid cartilages shaped like?
Pyramids
What are at the apex of the arytenoid cartilages?
The elastic corniculate cartilages
Why are the corniculate cartilages called that?
Because they are shaped like horns
Do the corniculate cartilages have a purpose?
No, they are considered vestigial structures
What is the epiglottis shaped like?
A leaf
Howis the epiglottis attached to the thyroid?
Via the thyroepiglottic ligament
How does the epiglottis act as a protective device?
By covering the larynx when swallowing to keep food from entering the trachea
What are the cuneiform cartilages embedded within?
The aryepiglottic folds
What do the cuneiform cartilages add to the aryepiglottic folds?
Stiffness
What are the two joints in the larynx?
Cricoarytenoid and cricothyroid
What connects the laryngeal cartilages to adjacent structures?
Extrinsic laryngeal membranes
What are the extrinsic laryngeal membranes?
The hyothyroid membrane, the paired hyothyroid ligaments, the hyoepiglottic ligament, and the cricotracheal membrane
The laryngeal cartilages connect to one another by what means?
Intrinsic laryngeal membranes
What are the intrinsic laryngeal membranes?
Conus elasticus membrane and quadrangular membrane
What do the conus elasticus membrane and the quadrangular membrane form what?
One broad sheet of connective tissue called the elastic membrane
What is triticeal cartilage?
A small cartilaginous nodule frequently found within the hyothyroid ligament
What suspends the thyroid cartilage from the hyoid bone?
Hyothyroid membrane
What connects the hyoid bone and the epiglottis?
The hyoepiglottic ligament
The hyoid is connected to the epiglottis by what ligament?
The hyoepiglottic ligament
The cricotracheal membrane connects what two structures?
The inferior border of the first tracheal ring and the cricoid cartilage
The hyoid bone is connected to the thyroid by what?
The hyothyroid membrane
The cricotracheal membrane connects what?
The inferior border of the first tracheal ring
The hyoid bone is connected to the thyroid by what?
The hyothyroid membrane
What is the broad elastic sheet that lines most of the larynx?
The elastic membrane
What is the lower portion of the elastic membrane called?
The conus elasticus
What is the upper portion of the elastic membrane called?
The quadrangular membrane
What is the conus elasticus shaped like?
A cone
Where does the conus elasticus lie?
Just below the level of the VFs
What is formed by the free thickened margins of the conus elasticus?
The vocal ligaments
Why are there not good pictures of the quadrangular membrane?
They are poorly defined
What forms the ventricular ligaments for the false vocal folds?
The inferior free thickened borders of the quadrangular membrane
What is the space between the true vocal folds called?
The glottis
What is the laryngeal cavity divided by?
The vocal folds into supraglottal and subglottal spaces
Where does the supraglottal region extend to and from?
From the aditus larygis (uppermost entrance to the larynx) to the glottis
Where does the subglottal region extent from and to?
From the superior level of the glottis to the inferior border of the cricoid cartilage
What are the ventricular folds also known as?
The false vocal folds
Where are the true VF in relation to the false VF?
They lie parallel to and just beneath the false VF
What are the true and false VF separated by?
The laryngeal ventricle
What is the anterior commissure?
The anterior junction point of the true vocal cords
What is the posterior commissure?
The posterior portion of the glottis
What is the glottis broken down into?
The membranous glottis (60%) and cartilaginous glottis (40%)
How big is the membranous glottis in males? Females?
15mm adult male, 12 mm adult female
How big is the cartilaginous glottis in males? Females?
8 mm males, slightly smaller in females
What are the muscles of the larynx divided into?
Intrinsic and extrinsic musculature
What is the extrinsic laryngeal musculature primarily responsible for?
Providing support to the larynx and fixing it in position
What is the intrinsic laryngeal musculature responsible for?
The control of sound production
What do the extrinsic laryngeal muscles consist of?
Sternothyroid, thyrohyoid, inferior pharyngeal constrictor muscles
What is the origin and insertion point of the sternothyroid muscle?
Origin - back surface of manubrium of the sternum; insertion - lower border of the body of the hyoid
What is the function of the sternothyroid muscle?
Pulling the thyroid cartilage downward
What is the origin and insertion of the thyrohyoid muscle?
Origin - oblique line of thyroid laminae; insertion - inferior border of greater cornu of hyoid bone
What is the primary function of the thyrohyoid muscle?
Depresses the hyoid and elevates the larynx
Where are the inferior pharyngeal constrictor muscles found?
At the base of the pharynx, and emanate from the thyroid and cricoid cartilages
When are the inferior pharyngeal constrictor muscles active and what do they form?
They are active during deglutition and form one of the principal resonance chambers of the voice
What is the function of the suprahyoid muscles?
They are layngeal elevators, when they contract, the elevate the larynx
What are the suprahyoid muscles also called and what does is include?
They are called laryngeal elevators and include the digastricus (ant. and post.), stylohyoid, mylohyoid, geniohyoid, hyoglossus, genioglossus
What do the digastricus muscles consist of?
Anterior belly and posterior belly
What is the function of the digastricus muscles?
They raise the hyoid bone, or if it is fixed, assist in lowering the mandible. Also assist with deglutition
Where is the stylohyoid muscle located?
It lies on top os the posterior digastic muscle
What is the origin and insertion of the stylohyoid muscle?
Origin - styloid process of temporal bone; insertion - it bifurcates to split the intermediate tendon of the digasticus muscle before inserting into hyoid bone
What is the function of the stylohyoid muscle?
Pulls the hyoid bone up and back
What does the mylohyoid muscle form?
The floor of the mouth
Where is the mylohyoid muscle?
It courses laterally from the mylohyoid line to the midline raphe (seam) The bottom fibers attach to corpus of the hyoid
What is the function of the mylohyoid muscle?
Depresses the mandible, elevates the jaw, assists deglutition
What is the mandibular symphysis?
The visible bump cuases by the junction of the two sides of the mandible
Where does the mylohyiod line run?
Along the inside edge of the mandible
