Larynx (dave's notes) Flashcards
Describe the larynx
A respiratory organ between the pharynx and trachea lying behind the hyoid bone.
What is the function of the larynx?
A protective sphincter and for phonation
What are the constituents of the larynx?
Cartilages, joints, ligaments and membranes
List the laryngeal cartilages
Three single: -thyroid -cricoid -epiglottic Three paired: -arytenoid -corniculate -cuneiform
List the laryngeal joints
Cricothyroid
Cricoarytenoid
Arytenocorniculate
List the extrinsic parts of the larynx
Thyrohyoid membrane
Cricotracheal
Hyoepiglottic
Thyroepiglottic
List the intrinsic parts of the larynx
Quadrangular membrane
Cricothyroid ligament
What type of cartilage are the laryngeal cartilages made of? What are the exceptions and what are these composed of?
Hyaline cartilage which may ossify/calcify with age
Exceptions are epiglottic, corniculate, and cuneiforms which are formed from elastic cartilage
Describe the structure of the thyroid cartilage
Two joined laminae with free posterior borders projecting as superior and inferior horns
What forms the adams apple? How else is this known?
The laryngeal prominence is formed by the anterior site of union of the thyroid laminae
Describe the cricoid cartilage
The only complete cartilage ring in the airway. Anteriorly an arch, posteriorly projected up as a quadrangular lamina
Describe the shape and attachments of the epiglottic cartilage. What prominence does it feature?
Leaf shaped, attached in the midline to the thyroid cartilage. The posterior prominence is enhanced by the overlying collection of mucous glands?
Where do the arytenoid cartilages sit? with what to they articulate? What does this achieve? What is their shape?
Pyramid shaped cartilages that sit posteriorly and articulate with the upper fodder of the lamina of the cricoid, giving attachment to the folds and muscles.
Where is the cricothyroid joint? What does movement achieve?
Posteriorly between the inferior horn of the thyroid cartilage and the facet on the side of the cricoid. Movement rocks one cartilage on top of the other.
Describe the capsule of the cricoarytenoid joint
A lax capsule allowing both rotatory and lateral gliding movements
What does the thyrohyoid membrane connect?
The whole length of the upper border of the thyroid laminae and part of the hyoid.
What occurs in the midline of the thyrohyoid membrane? Where on the hyoid does the membrane attach?
The midline thickens to form the median thyroihyoid ligament. The membrane passes up behind the hyoid to attach to its upper border
What recess is completed by the thyrohyoid membrane? What perforates it?
The thyrohyoid membrane forms the lateral wall of the piriform recess.
It is perforated by the internal laryngeal nerve and the superior laryngeal vessels
List the epiglottic attachments. (5)
Midline attachment to the thyroid cartilage - thyroepiglottic ligament.
Attached to the arytenoid cartilages by the aryepiglottic folds
Attached to the tongue by the median epiglottic fold.
Further joint to the hyoid bone (by the hyoepiglottic ligament)
What connects the lower border of cricoid cartilage to the first cartilaginous ring?
The cricotracheal ligament
Where is the quadrangular membrane attached?
Extends between the arytenoid cartilages and the epiglottis
Describe the cavities of the larynx
The adieus faces backwards bound by the epiglottis
Aryepiglottic folds
Interarytenoid fissure
What is the rima of the glottis? What and where is the gap at rest?
An AP slit (60% vocal fold, 40% vocal process). The posterior gap at rest is 8mm.
What are they most important muscles of the larynx?
The posterior cricoarytenoids as they are the only ones that abduct the vocal cords. See text.
What does cricothyroid contraction cause?
The anterior parts to approach, this lengthens the cords.
