Muscles - The Tongue Flashcards
What are the intrinsic muscles of the tongue?
There are four paired intrinsic muscles of the tongue:
1) Superior longitudinal
2) Inferior longitudinal
3) Transverse
4) Vertical
Innervation of the intrinsic muscles of the tongue
Hypoglossal nerve (CN XII)
Actions of the intrinsic muscles of the tongue?
1) Speech
2) Eating
3) Swallowing
What are the extrinsic muscles of the tongue?
1) Palatoglossus
2) Styloglossus
3) Genioglossus
4) Hyoglossus
Mnemonic - Paris St Germain’s hour
Palatoglossus
Origin - palatine aponeurosis
Insertion - tongue
Action - elevates posterior tongue
Innervation - motor innervation of CN X - the odd one out
Styloglossus
Origin - styloid process
Insertion - side of tongue
Action - retracts and elevates the tongue
Innervation - motor hypoglossal nerve
Genioglossus
Origin - mandibular symphysis
Insertion - hyoid bone - covers length of the tongue
Action -
1) inferior fibres - protrude the tongue
2) middle fibres - depress tongue
3) superior fibres - draws the tip back and down.
Innervation - motor hypoglossal nerve
Hyoglossus
Origin - hyoid bone
Insertion - side of the tongue
Action - depresses and retracts tongue
Innervation - motor hypoglossal nerve
Innervation
Anterior 2/3 tongue -
Taste - facial nerve (superior salivatory nucleus)
General sensory - mandibular nerve (lingual nerve)
Posterior 1/3 tongue -
Taste and general sensory - glossopharyngeal nerve
Vasculature
Lingual artery (a branch of the ECA)
Tonsillar artery (a branch of the facial artery)
Drainage by lingual vein
Lymphatic drainage
Anterior 2/3 - submental and submandibular lymp nodes that drain into the deep cervical lymph nodes.
Posterior 1/3 - deep cervical lymph nodes.
Clinical relevance - tongue tied?
Anteroinferiorly at the midline of the tongue is the frenulum.
Excess frenulum can result in a person being ‘tongue-tied’.
This can be managed with surgery.
