Muscle Actions Flashcards
What are the actions of the Frontal Belly of Occipitofrontalis?
1) Elevate eyebrows
2) Wrinkles skin of forehead
What are the actions of the Orbicularis Oculi?
Closes eyelids
What are the actions of the Platysma?
1) Depresses mandible
2) Tense skin of lower face and neck
What are the actions of the orbicularis oris?
1) Tonus closes oral fissure
2) Phasic contraction compresses and protrudes lips (kissing)
3) Resists distension (when blowing)
What are the actions of Levator anguli oris?
Elevates corners of mouth
What are the actions of depressor labii inferioris?
1) Depresses lower lip and/or
2) Everts lower lip

What are the actions of the depressor anguli oris?
1) Depresses angles of mouth

What are the actions of zygomaticus major?
Elevate angle of mouth
What are the actions of risorius?
Draw corner of mouth laterally
What are the actions of levator labii superioris?
1) Retract (elevate) upper lip
and/or
2) Evert upper lip

What are the actions of the masseter?
1) Elevate mandible,
2) Closing jaws
3) Limited protrusion of mandible

What is the action of the buccinator?
Keep cheek taut

What is the action of Inferior Oblique?
Abducts elevates laterally rotates eyeball

What is the action of Inferior Rectus?
Depresses adducts rotates eyeball laterally

What is the action of Lateral Rectus?
Abducts eyeball

What is the action of Levator Palpebrae Superioris?
Elevates superior eyelid

What is the action of Medial Rectus?
Adducts eyeball

What is the action of Orbicularis Oculi?
Closes eyelids
What is the action of Superior Oblique?
Abducts, depresses medially rotates eyeball

What is the action of Superior Rectus?
Elevates adducts rotates eyeball medially

What is the action of Tensor Tympani?
Pull handle of malleus medially to tense the tympanic membrane

What is the action of Stapedius?
Pulls stapes posteriorly, tightening anular ligament and reducing oscillatory range

What is the action of Levator Scapulae?
Elevate scapula, tilt glenoid cavity inferiorly

What is the action of Omohyoid?
Depresses, retracts, and steadies hyoid

What is the action of Platysma?
Depress mandible, tense skin of lower face and neck

What are the actions of the Scalenes?
- Anterior: flex head
- Middle: flex head and elevate 1st rib during forced inspiration
- Posterior: flex head and elevate 2nd rib during forced inspiration
