Axial Muscles Flashcards
What is the epicranius composed of?
- epicranial aponeurosis
- occipital frontalis muscle
What are the actions of the frontal belly of occipitofrontalis?
- moves scalp and eyebrows
- wrinkles skin of forehead
Where is the origin of the frontal belly of occipitofrontalis?
frontal bone
Where is the insertion of the frontal belly of occipitofrontalis?
epicranial aponeurosis
What are the actions of the occipital belly of occipitalfrontalis?
retracts scalp
Where is the origin of the occipital belly of occipitalfrontalis?
superior nuchal line
Where is the insertion of the occipital belly of occipitalfrontalis?
epicranial aponeurosis
What are the actions of the depressor anguli oris?
draws corners of mouth inferiorly and laterally (“frown” muscle)
Where is the origin of the depressor anguli oris?
body of mandible
Where is the insertion of the depressor anguli oris?
skin at inferior corner (angle) of mouth
What are the actions of the orbicularis oris?
compresses and purses lips (“kiss” muscle)
Where is the origin of the orbicularis oris?
- maxilla and mandible
- blend with fibres from other facial muscles
Where is the insertion of the orbicularis oris?
- encircling mouth
- skin and muscles at angles to mouth
What are the actions of the zygomaticus major?
elevates corner of the mouth (“smile” muscle)
Where is the origin of the zygomaticus major?
zygomatic bone
Where is the insertion of the zygomaticus major?
skin at superolateral edge of mouth
What are the actions of the orbicularis oculi?
- closes eye
- produces winking, blinking, squinting (“blink” muscle)
Where is the origin of the orbicularis oculi?
medial wall or margin of orbit
Where is the insertion of the orbicularis oculi?
skin surrounding eyelids
What are the actions of the platysma?
- pulls lower lip inferiorly
- tenses skin of neck
Where is the origin of the platysma?
fascia of deltoid and pectoralis major muscles and acromion of scapula
Where is the insertion of the platysma?
skin of cheek and mandible
What are the actions of the temporalis?
elevates and retracts mandible
Where is the origin of the temporalis?
superior and inferior temporal lines
Where is the insertion of the temporalis?
coronoid process of mandible
What are the actions of the masseter?
- elevates and protracts mandible
- prime mover of jaw closure
Where is the origin of the masseter?
zygomatic arch
Where is the insertion of the masseter?
coronoid process, lateral surface and angle of mandible
What are the actions of the medial pterygoid?
- elevates and protracts mandible
- produces side-to-side movement of mandible
Where is the origin of the medial pterygoid?
maxilla, palatine, and medial surface of lateral pterygoid plate
Where is the insertion of the medial pterygoid?
medial surface of mandibular ramus
What are the actions of the lateral pterygoid?
- protracts mandible
- produces side-to-side movement of mandible
Where is the origin of the lateral pterygoid?
greater wing of sphenoid and lateral surface of lateral pterygoid plate