Tongue (dave's notes) Flashcards
Describe the tongue
A mass of skeletal muscle covered with mucous membrane, with a midline fibrous septum
What are the parts of the tongue?
The dorsum (upper surface)
The tip (most anterior)
The inferior surface
The root
What is significant about the mucous membrane of the tongue?
The mucous membrane of the oral and pharyngeal parts have different developmental origins and surface appearances
What is the anterior 2/3 of the tongue covered with? What occurs here?
Mucous membrane, into which the underlying muscles are inserted
What is the epithelium type on the anterior two thirds of the tongue?
Mucous membrane with stratified squamous epithelium of a keratinising variety.
Other than mucous membrane, what is found on the anterior 2/3rs of the tongue? What type of glands?
The anterior 2/3rds is roughened with papillae. There are no glands on the dorsum of the anterior 2/3rds of the tongue.
What types of papillae are found on the anterior 2/3rds of the tongue?
Filiform, fungiform and vallate (v-shape)
Describe the posterior 1/3rd of the tongue
Post sulcal, really a part of the pharynx from the sulcus terminals to the epiglottis
What is found at the apex of the sulcus between the anterior 2/3rds and the posterior 1/3rd?
The foramen caecum, the remains of the thyroglossal duct
What types of papillae and glands are found in the posterior 1/3rd of the tongue, behind the sulcus? What appearance does this region have?
Nodular appearance from the presence of underlying mucous and serous glands. There are no papillae behind the sulcus.
What two types of muscles are found in the tongue?
Intrinsic - wholly within the tongue, not attached to any bones
Extrinsic - attached to bone
List the intrinsic muscles of the tongue.
Superior and inferior longitudinal, transverse and vertical
List the extrinsic muscles of the tongue
Genioglossus, hyoglossus, styloglossus, palatoglossus
Which is the largest extrinsic muscle of the tongue? Where does it attach?
Genioglossus; also connects to the hyoid bone
From what does hyoglossus arise? What does it interdigitate with?
Arises from the length of the greater horn of the hyoid, with the upper borders interdigitating with styloglossus.
Describe the anterior and posterior borders of hyoglossus
These are free
What are the lateral relations of hyoglossus?
Lateral and superficial to hyoglossal, from superior to inferior:
Lingual nerve,
Submandibular duct
Hypoglossal nerve
What are the deep relations of hyoglossus?
From above downwards:
Glossopharyngeal nerve
Styloid ligament
Lingual artery
What are the attachments of styloglossus?
From the lower part of the styloid process and the upper part of the stylohyoid ligament
What does styloglossus pass below?
The superior constrictor to the side of the tongue
What are the attachments of palatoglossus?
From the palatine aponeurosis to the side of the tongue
What do the attachments of palatoglossus create?
The palatoglossal arch
What is the blood supply to the tongue?
The lingual artery
What is the venous drainage of the tongue?
Via tributaries to the lingual vein, to the internal jugular vein
What is the nerve supply to the muscles of the tongue?
All muscles are supplied by the hypoglossal nerve except palatoglossal which is innervated by the pharyngeal plexus
What is the innervation of the vallecula?
Sensory, from the internal laryngeal nerve
What is the sensory innervation to the posterior one third of the tongue?
Glossopharyngeal nerve, sense, taste and parasympathetic
What is the sensory innervation to the anterior 2/3rds of the tongue?
Lingual nerve, trigeminal sense, CT (facial) taste - also carries parasympathetic fibres for the glands.
