TONGUE | INTRINSIC MUSCLES / EXTRINSIC MUSCLES / ORIGIN , INSERTION AND ACTIONS OF INTRINSIC AND EXTRINSIC MUSCLES OF TONGUE

 

#Muscles of tongue are divided into two groups.

1) Extrinsic muscles

2) Intrinsic muscles

Q : What are extrinsic muscles of tongue ?

* Extrinsic muscles of tongue include :

1) Genioglossus

2) Hyoglossus

3) Styloglossus

4) Palatoglossus

Q :What are intrinsic muscles of tongue ?

1) Superior longitudinal muscle

2 ) Inferior longitudinal muscle

3) Transverse lingual muscle

4) Vertical linguae muscle 

Q : Write about Origin , insertion and actions of intrinsic and extrinsic muscles of tongue ?

* Extrinsic muscles alter position of the tongue.

* Intrinsic muscles alter shape of the tongue.

# EXTRINSIC MUSCLES OF TONGUE :

1) GENIOGLOSSUS :

ORIGIN : Superior genial tubercles on symphysis menti

INSERTION : 

1) lower fibres insert into hyoid bone.

2) Middle fibres are continuos with middle constrictor of pharynx.

3) Upper fibres are attached to the sides of the tongue from apex to root.

ACTIONS : protudes tip of the tongue , making dorsal surface concave

2) HYOGLOSSUS :

ORIGIN : greater cornu and adjacent part of body of hyoid.

INSERTION : lateral part of the tongue in between inferior longitudinal muscle of tongue medially and styloglossus laterally.

ACTIONS : depresses sides of the tongue and make the dorsal surface convex.

3) STYLOGLOSSUS 

ORIGIN : tip of the styloid process and stylomandibular ligament.

INSERTION : inserts into sides of the tongue.

ACTIONS : retracts the tongue backwards and upwards.

4) PALATOGLOSSUS 

ORIGIN :  oral surface of Palatine aponeurosis.

INSERTION : inserts into sides of the tongue.

ACTIONS : pulls up the root of the tongue , approximates palatoglossal arches.

INTRINSIC MUSCLES OF TONGUE :

1) SUPERIOR LONGITUDINAL MUSCLE :

ORIGIN : posterior part of median fibrous septum of tongue.

INSERTION : inserts into sides of the tongue.

ACTION : reduces the length of the tongue and makes dorsal surface concave.

2) INFERIOR LONGITUDINAL MUSCLE :

ORIGIN : Sides of the tongue posteriorly.

INSERTION : anterior part of median fibrous septum.

ACTION : shortens tongue , makes dorsal surface convex.

3) TRANSVERSE LINGUAL MUSCLE :

ORIGIN : arises from median fibrous septum .

INSERTION : inserts into sides of the tongue

ACTION : reduces width and increases length of the tongue.

4) VERTICAL LINGUAE MUSCLE :

ORIGIN : lamina propria of dorsum of the tongue.

INSERTION : inserts into sides of the tongue.

ACTION :  increases width of tongue and makes dorsal surface concave.