Larynx (dave's notes)

Question 1

Describe the larynx

Answer 1

A respiratory organ between the pharynx and trachea lying behind the hyoid bone.

Question 2

What is the function of the larynx?

Answer 2

A protective sphincter and for phonation

Question 3

What are the constituents of the larynx?

Answer 3

Cartilages, joints, ligaments and membranes

Question 4

List the laryngeal cartilages

Answer 4

Three single:
-thyroid
-cricoid
-epiglottic
Three paired:
-arytenoid
-corniculate
-cuneiform

Question 5

List the laryngeal joints

Answer 5

Cricothyroid
Cricoarytenoid
Arytenocorniculate

Question 6

List the extrinsic parts of the larynx

Answer 6

Thyrohyoid membrane
Cricotracheal
Hyoepiglottic
Thyroepiglottic

Question 7

List the intrinsic parts of the larynx

Answer 7

Quadrangular membrane

Cricothyroid ligament

Question 8

What type of cartilage are the laryngeal cartilages made of? What are the exceptions and what are these composed of?

Answer 8

Hyaline cartilage which may ossify/calcify with age

Exceptions are epiglottic, corniculate, and cuneiforms which are formed from elastic cartilage

Question 9

Describe the structure of the thyroid cartilage

Answer 9

Two joined laminae with free posterior borders projecting as superior and inferior horns

Question 10

What forms the adams apple? How else is this known?

Answer 10

The laryngeal prominence is formed by the anterior site of union of the thyroid laminae

Question 11

Describe the cricoid cartilage

Answer 11

The only complete cartilage ring in the airway. Anteriorly an arch, posteriorly projected up as a quadrangular lamina

Question 12

Describe the shape and attachments of the epiglottic cartilage. What prominence does it feature?

Answer 12

Leaf shaped, attached in the midline to the thyroid cartilage. The posterior prominence is enhanced by the overlying collection of mucous glands?

Question 13

Where do the arytenoid cartilages sit? with what to they articulate? What does this achieve? What is their shape?

Answer 13

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.

Question 14

Where is the cricothyroid joint? What does movement achieve?

Answer 14

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.

Question 15

Describe the capsule of the cricoarytenoid joint

Answer 15

A lax capsule allowing both rotatory and lateral gliding movements

Question 16

What does the thyrohyoid membrane connect?

Answer 16

The whole length of the upper border of the thyroid laminae and part of the hyoid.

Question 17

What occurs in the midline of the thyrohyoid membrane? Where on the hyoid does the membrane attach?

Answer 17

The midline thickens to form the median thyroihyoid ligament. The membrane passes up behind the hyoid to attach to its upper border

Question 18

What recess is completed by the thyrohyoid membrane? What perforates it?

Answer 18

The thyrohyoid membrane forms the lateral wall of the piriform recess.
It is perforated by the internal laryngeal nerve and the superior laryngeal vessels

Question 19

List the epiglottic attachments. (5)

Answer 19

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)

Question 20

What connects the lower border of cricoid cartilage to the first cartilaginous ring?

Answer 20

The cricotracheal ligament

Question 21

Where is the quadrangular membrane attached?

Answer 21

Extends between the arytenoid cartilages and the epiglottis

Question 22

Describe the cavities of the larynx

Answer 22

The adieus faces backwards bound by the epiglottis
Aryepiglottic folds
Interarytenoid fissure

Question 23

What is the rima of the glottis? What and where is the gap at rest?

Answer 23

An AP slit (60% vocal fold, 40% vocal process). The posterior gap at rest is 8mm.

Question 24

What are they most important muscles of the larynx?

Answer 24

The posterior cricoarytenoids as they are the only ones that abduct the vocal cords. See text.

Question 25

What does cricothyroid contraction cause?

Answer 25

The anterior parts to approach, this lengthens the cords.