Pharynx - Inferior constrictor (dave's notes) Flashcards
What are the parts of the inferior constrictor?
Thyropharyngeus and cricopharyngeus
Where does thyropharyngeus arise?
From the oblique line of the thyroid cartilage
Where does cricopharyngeus arise and run to?
Runs uninterrupted from one side of the cricoid arch to the other with no raphe.
What is the action of cricopharyngeus? With what is it continuous?
Acts as a sphincter. Continuous with the oesophagus. Always closed except during swallowing.
Where may a pharyngeal diverticulum develop?
At the junction of cricopharyngeus and thyropharyngeus
Describe the course of palatopharyngeus
Palatopharyngeus fibres pass internal to the superior constrictor
Describe the course of salpingopharyngeus
Arises from the lower part of the auditory tube and blends with palatopharyngeus
Describe the origin and path of stylopharyngeus
Arises high up on the styloid process sloping down across the internal carotid artery
What is the blood supply to the inferior constrictor?
Many different sources
Describe the venous drainage of the inferior constrictor
By the pharyngeal plexus (at the back of the middle constrictor) draining to the pterygoid plexus or to the internal jugular vein
Where does inferior constrictor lymph drain to?
Retropharyngeal nodes, to the upper and lower deep cervical nodes.
What is the nerve supply to the pharynx? What is the exception to this?
Via the pharyngeal plexus, except stylopharyngeus which is by theglossopharyngeal nerve, and criopharyngeus may be supplied by the recurrent laryngeal nerve.
Where are the cell bodies to the six muscles found?
The nucleus ambiguous
Where is the pharyngeal plexus found?
In the posterolateral wall of the pharynx (the middle constrictor).
What nerves contribute to the pharyngeal plexus?
Formed by the vagus, glossopharyngeal, and cervical sympathetic
