What nerve gives of pharyngeal branches?
-Vagus nerve gives of pharyngeal branches
What action does the arytenoid do when formulating a vowel sound?
Do a pivoting action when formulating vowel sounds
What is the action of cricothyroid muscles?
Lengthening (increasing tension) of vocal ligaments
What is the action of the posterior cricoarytenoid muscles?
Abduction of vocal ligaments
What is the action of the lateral cricoarytenoid muscles?
Adduction of vocal ligaments
What is the action of transverse and oblique arytenoid muscles?
Adduction of vocal ligaments
What is the action of vocalis and thyroarytenoid muscles?
Shortening(relaxation) of vocal ligaments
What does the recurrent laryngeal nerve innervate?
- Posterior and lateral crico-arytenoid
- Oblique and transverse arytenoid
- Vocalis and thyro-arytenoid
What nerve innervates the cricothyroid muscle?
Cricothyroid muscle is innervated by the superior laryngeal nerve
What happens to the vocal folds, rima glottidis and vestibule during forced inspiration?
- Vocal folds abducted and rima glottidis wide open
- Vestibule open
What happens to the vocal folds and vestibule during phonation?
- Vocal folds adducted and stridulating as air is forced between them
- Vestibule open
What happens to the laryngeal and epiglottis during swallowing?
- Laryngeal inlet narrowed
- Epiglottis swings down to arytenoids
What happens to the vocal folds, rima glottidis and vestibule during effort closure?
- Vocal folds and vestibular folds adducted
- Rima glottidis and vestibule closed
What does the superior laryngeal nerve go through and supply?
Superior laryngeal nerve goes through aperture of the thyroid membrane and supply posterior cricothyroid muscle
What is a cricothyroidotomy?
-An emergency procedure to obtain an airway when other routine methods are ineffective
What causes the procedure of cricothyroidotomy to take place?
This takes place due to trauma causing oral, pharyngeal or nasal haemorrhage
Where do thyroid glands sit
-Thyroid gland sits on the trachea
What do strap muscles protect?
Strap muscle allows protection of the thyroid gland
How many parathyroid glands are there and where are they in relation to the thyroid gland?
4 parathyroid glands that are posterior to the thyroid gland
What are the parathyroid glands important in?
Parathyroid Important in calcium regulation
What are the steps involved in thyroid development?
- Thyroid gland begins to develop as a median thickening of endoderm on the floor of the pharynx between the first and second pharyngeal pouches
- This area later invaginates to form the median diverticulum
- This thyroid diverticulum grows becoming the thyroglossal duct.
- Thyroglossal duct grows caudally and bifurcates to give rise to the thyroid lobes and the isthmus
What do remnants of the thyroglossal duct persist as?
-The thyroglossal duct usually disappears early in development but remnants persist as a cyst or as a connection to the foramen cecum (Fistula).
What is a fistula?
Fistula is the connection between one surface of one structure to another surface of another structure
