Hyoid, larynx and swallowing Flashcards
What is the function of the hyoid apparatus?
Suspends the tongue and larynx from the base of the skull
Which part of the hyoid is the unpaired body?
Basihyoid
Which two muscles of the hyoid apparatus draw the hyoid caudally?
- Sternohyoideus
- Thyrohyoideus
Which two muscles of the hyoid apparatus draw the hyoid rostrally?
- Mylohyoideus
- Geniohyoideus
What is the primary role of the larynx?
Protect the lower respiratory tract from foreign bodies
Which 3 parts make up the beginning of the airway?
- The vestibule
- The glottis
- The infraglottic cavity
What are the 4 cartilages of the larynx, which one is paired?
- Thyroid
- Epiglottis
- Arytenoid - paired
- Cricoid
What hold the cartilages in place?
Mucosal folds of the larynx
There are 8 pairs of laryngeal muscles, how many are involved in closing the glottis and how many are involved in opening it?
7 pairs close
1 pair opens
What is the nerve supply to the larynx?
From the vagus accessory complex - CNX and XI
What are the two main branches from the vagus accessory complex?
- Cranial laryngeal nerve
2. Recurrent laryngeal nerve
Which nerves are responsible for the part of the afferent innervation which initiates swallowing?
Glossopharyngeal and vagus
Name some of the paired bones of the hyoid
- Epihyoid
- Stylohyoid
- Keratohyoid
- Thyrohyoid
Name the 4 main muscles of the hyoid apparatus
- Sternohyoideus
- Thyrohyoideus
- Mylohyoidesus
- Geniohyoieus
What is the secondary role of the larynx?
Voice production
Which 2 laryngeal muscles are of important, what are their functions?
Cricoarytenoideus dorsalis – abducts the arytenoids and opens the glottis.
Cricoarytenoideus lateralis – one of several muscles that close the glottis
Describe the steps involved in swallowing
- Bolus squeezed caudally into the oral pharynx by the tongue against the palate
- Projected into the common pharynx which squeezes the bolus caudally and the glottis is closed
- The oesophageal pharynx squeezes the bolus towards the oesophageal sphincter. The soft palate returns ventrally. Glottis reopens
The peristaltic muscular movements are under what kind of control?
Reflex
Which nerves supply the efferent nerves of the swallowing reflex?
The vagus-accessory complex, via the pharyngeal nerve of the vagus
