Muscles part 1

Cranial nerve VII Facial nerve branches:

temporal, zygomatic, buccal, mandibular

Passes through the parotid salivary gland.

FACIAL Nerve VII

Epicranius Frontal Belly origin

Epicranial aponeurosis.

Epicranius Frontal Belly insertion

Skin of eyebrow and root of nose.

Epicranius Occipital Belly insertion

Epicranial aponeurosis.

Epicranius Occipital Belly origin

Superior nuchal line, mastoid process.

Epicranial muscle action

Raise the eyebrows and scalp. Bellies can act independently.

Orbicularis oculi origin

Orbital rim, Frontal bone, Maxilla.

Orbicularis oculi insertion

Skin at the lateral canthus. Some fibers encircle the orbit.

Orbicularis oculi action

Closes the eyelid, Blinking, Squinting.

Corrugator supercilii origin

Frontal bone, Supraorbital region.

Corrugator supercilii insertion

Skin of the eyebrow.

Corrugator supercilii action

Draws the eyebrow in and downward

3 muscles of the nasal region…

nasalis, procerus, depressor septi nasi

The ______ is the largest and best developed of the group of nasal region muscles, which is active when the nares are flared.

Kissing muscle

Orbicularis oris.

Orbicularis oris origin

Encircle the mouth between the skin and labial mucosa of lips. No bony attachment.

Orbicularis oris insertion

Skin of the lips at both labial commissures.

Orbicularis oris action

Closing lips, Pursing lips, Grimacing, Pouting and kissing.

Thin quadrilateral muscle that forms the anterior part of the cheek or the lateral wall within the buccal region of the oral cavity.

Buccinator

Buccinator origin

Alveolar processes of maxillae and mandibule, Pterygomandibular fold/raphe.

buccinator insertion

maxilla/superior of pterygomandibular raphe inserts obliquely downward into lower lip, mandible/inferior of pterygomandibular raphe inserts obliquely upwards into upper lip

Buccinator muscle action

Pulls labial commissures laterally, shortening the cheek, Aids in chewing by keeping food in correct position.

what is the buccinator muscle known as?

the trumpet muscle

Risorius origin

Fascia over masseter.

Risorius insertion

Skin at labial commissure.

Risorius action

Stretches lip laterally, Retracts labial commissure, widening the mouth.

grimace muscle

Risorius.

Levator labii superioris origin

Infraorbital rim of the maxilla.

Levator labii superioris insertion

Skin of the upper lip.

Levator labii superioris action

Elevates the upper lip.

Levator labii superioris alaeque nasi origin

Frontal process of the maxilla.

Levator labii superioris alaeque nasi insertion

The skin of the ala of the nose, Upper lip.

Levator labii superioris alaeque nasi action

Elevates the upper lip and the ala of the nose, thus dilating each nares.

Sneering muscle

Levator labii superioris alaeque nasi.

zygomaticus major origin

zygomatic bone

zygomatic major insertion

labial commissure

Zygomaticus major action

Elevates the labial commissure and pulls it laterally.

Zygomaticus minor origin

Zygomatic bone.

Zygomaticus minor insertion

Skin of the upper lip.

Zygomaticus minor action

Elevates the upper lip.

Depressor anguli oris origin

Mandible.

Depressor anguli oris insertion

Labial commissure.

Depressor anguli oris action

Depresses the labial commissure.

what is the depressir anguli oris known as?

the frowning muscle

depressor labii inferioris origin

mandible

depressor labii inferioris insertion

lower lip

depressor labii inferioris action

depresses the lower lip, exposing the mandibular teeth

what is the depressir labii inferios muscle referred to as?

irony muscle, facial expressions of sarcam

mentalis muscle origin

mandible

mentalis msucle insertion

chin

mentalis muscle action

raises the chin causing the lip to protrude

Origin

The end attached to the least movable structure.

Insertion

The end attached to the more movable structure.

Sternocleidomastoid origin

Clavicle and sternum.

Sternocleidomastoid insertion

Mastoid process, superior nuchal line.

Sternocleidomastoid action

If one muscle contracts, head and neck bend to unilateral side, face and front of the neck rotate to contralateral side. If both muscles contract the head will flex at the neck and extend at the junction between the neck and skull.

Trapezius origin

Occipital bone, cervical and thoracic regions.

Trapezius insertion

Clavicle, scapula.

Trapezius action

Lift the clavicle and scapula, As when the shoulders are shrugged.

May be the first sign of damage to the seventh cranial (facial) nerve.

Inability to form facial expressions

Pterygomandibular fold

Tendinous band located posterior to the most distal mandibular molar.

Platysma origin

Skin clavicle and shoulder.

Platysma insertion

Mandible and muscles of mouth.

Platysma action

Vertical, horizontal ridges and depression in neck skin. Pulls labial commissures down.

SCM is innervated by….

accessory nerve (XI)

trapezius is innervated by»»

accessory nerve (XI), as well as 3rd and 4th