Muscles - Facial Expression Flashcards
Embrological origin of the facial muscles?
2nd pharyngeal arch.
Innervation of facial muscles?
Facial nerve.
Occipitofrontalis
Attachments?
Actions?
Branch of facial nerve?
Origin (frontal belly) - epicranial aponeurosis
Insertion (frontal belly) - skin of eyebrows; root of nose
Actions - raise eyebrows; wrinkles forehead
Innervation - Temporal branch
Orbicularis Oris
Attachments?
Actions?
Branch of the facial nerve?
Origin - medial orbital margin; medial palpebral ligament; lacrimal bone.
Inserts - skin around the margin of the orbit; superior and inferior tarsal plates.
Action:
Palpebral part - gently closes eyelids.
Lacrimal part - involved in drainge of tears.
Orbital parts - closes eyelid tightly.
Branch of the facial nerve - temporal.
Corrugator supercilli
Attachments?
Actions?
Innervations?
Origin - superciliary arch, running in superolateral direction.
Insertion - skin of the eyebrow.
Action - draws eyebrow together (creates vertical wrinkles of the bridge of the nose.
Branch of the facial nerve - temporal
Clinical relevance - paralysis of the orbital group muscles
If the facial nerve is damaged, the muscles will cease to work:
1) Eye cannot shut - cornea dries out - exposure keratitis.
2) Lower eyelid droops - ectropion - lacrimal fluid pools in the lower eyelid - failure to spread tears across eye - can result in failure to remove debris and ulceration of the corneal surface.
Test for facial nerve palsy - ask patient to close eyelids and raise eyebrows.
Nasalis
Attachments?
Actions?
Origin - maxilla
Insertion:
Transverse part - aponeurosis across the dorsum of the nose.
Alar part - alar cartilage of the nasal skeleton.
Actions -
Transverse part - compresses nares.
Alar part - flares nares.
Procerus
Attachments?
Actions?
Origin - nasal bone
Insertion - lower medial forehead
Actions - Contraction pulls eyebrows down, producing transverse wrinkles over nose.
Depressor septi nasi
Attachments?
Actions?
Origin - maxilla (above the medial incisor)
Insertion - nasal septum
Action - assists the alar part of the nasalis to flare the nostrils - pulls the nose inferiorly.
Zygomatic minor
Attachments?
Actions?
Branch of the facial nerve?
Origin - lateral surface of the zygomatic bone.
Insertion - angle of the mouth
Action - elevates the upper lip
Branch - zygomatic
Zygomatic major
Attachments?
Actions?
Branch of the facal nerve?
Origin - zygomatic bone
Insertion - angle of the mouth
Actions - elevates the angle of the mouth
Branch - zygomatic
Levator labii superioris
Attachments?
Actions?
Branch of the facial nerve?
Origin - infraorbital margin
Insertion - subcutaneous tissue of the upper lip
Actions - elevates and everts upper lip
Branch - zygomatic
Orbicularis oris
Attachments?
Actions?
Branch of the facial nerve?
Origin - maxilla and other muscles of the cheek
Insertion - skin and mucous membranes of the lip
Action - purses the lips
Branch - buccal
Buccinator
Attachments?
Actions?
Branch of the facial nerve?
Origin - maxilla and mandible, running inferomedially
Insertion - blends with the orbicularis oris and the skin of the lips.
Actions - pulls the cheek towards the teeth when eating
Branch - buccal
Risorius
Attachments?
Actions?
Branch of the facial nerve?
Origin - parotid fascia
Insertion - modiolus; skin overlying the angle of the mouth
Actions - pulls the angle of mouth laterally
Branch - buccal
Mentalis
Attachments?
Actions?
Branch of the facial nerve?
Origin - incisive fossa of mandible
Insertion - subcutaneous tissue of the chin
Actions - elevates and protrudes the lower lip
Branch - marginal mandibular
