Muscles of Face & Neck

Question 1

Anterior Belly Digastric

Answer 1

Innervated by Mylohyoid Nerve (branch of CN V3)

Anterior Inferior mandible –> fibrous loop above Hyoid bone. Form lateral boundaries of submental triangle of neck, medial boundaries of digastric (submandibular) triangle.

Elevates hyoid bone

Question 2

Posterior Belly Digastric

Answer 2

Innervated by Facial Nerve

Posterior inferior mandible –> fibrous loop above Hyoid bone. Form posterior boundary of digastric (submandibular triangle). Form superior boundary of carotid triangles.

Elevates hyoid bone

Question 3

Superior Belly Omohyoid

Answer 3

Innervated by Ansa Cervicalis (C1,2,3)

Hyoid –> Intermediate tendon (which is attached to clavicle & first rib). Forms medial boundary of carotid triangle. Forms lateral boundary of muscular triangle.

Depresses hyoid bone

Question 4

Inferior Belly Omohyoid

Answer 4

Innervated by Ansa Cervicalis (C1,2,3)

Superior border of scapula –> intermediate tendon (which is attached to clavicle & first rib)

Depresses hyoid bone

Question 5

Thyrohyoid

Answer 5

Innervated by nerve to thyrohyoid (C1) (piggybacks on CN12)

Thyroid cartilage –> hyoid bone

Depress hyoid bone/elevate thyroid cartilage

Question 6

Geniohyoid

Answer 6

Innervated by nerve to geniohyoid (C1) (piggybacks on CN12)

Chin –> hyoid bone

Elevate hyoid bone/depress mandible

Question 7

Splenius Capitus

Answer 7

Innervated by dorsal rami of C3 and C4

Spinous processes of C7-T3 –> Mastoid process of temporal bone. Superior portion of roof of posterior triangle of neck.

Head extension, lateral rotation and flexion of cervical spine.

Question 8

Levator Scapulae

Answer 8

Innervated by Dorsal Scapular n.

Transverse processes of C1-4 –> medial border of scapula. Runs in floor of posterior triangle of neck, between Splenius Capitus & scalenes.

Elevates scapula.

Question 9

Scalenes (posterior, middle, anterior)

Answer 9

Innervated by C3-C7

Transverse processes of cervical vertebrae –> first & second ribs.

Runs in floor of inferior portion of posterior triangle of neck.

Lift first & second ribs, laterally flex neck to same side.

Question 10

Sternohyoid

Answer 10

Innervated by Ansa Cervicalis (C1-C3)

Sternum –> Hyoid

Depress Hyoid

Question 11

Sternothyroid

Answer 11

Innervated by Ansa Cervicalis (C1-C3)

Sternum –> Thyroid cartilage

Depress thyroid cartilage, and indirectly depress hyoid.

Question 12

Mylohyoid

Answer 12

Innervated by nerve to Mylohyoid (branch of CNV3)

Sheet like. Entire length of inner mandible –> Hyoid bone

Elevate Hyoid bone.

Stylohyoid & Digastric muscles are superficial to MH. Geniohyoid is deep to MH.

Question 13

Stylohyoid

Answer 13

Innervated by Facial Nerve (CN7)

Styloid process of temporal bone –> Hyoid bone.

Anterior and Superficial to Post belly of digastric.

Elevate Hyoid bone.

Question 14

Orbicularis oculi

Answer 14

CN7

Completely surrounds each orbit.

Orbital part- surrounding orbit and beyond rim. Closes eye forcefully.

Palpebral part. In eyelids. Originate medially, attach laterally. Close eye gently.

Question 15

Corrugator supercilii

Answer 15

CN7

Deep to eyebrows.

Draws eyebrows down and medial, wrinkles skin above nose during frowning. >:(

Question 16

Nasalis

Answer 16

CN7

Transverse part- on superior/lateral part of nose itself. Compresses nares.

Alart part. Inferior/lateral to nose. Depresses and pulls alar cartilage laterally- opens nares.

Question 17

Procerus

Answer 17

CN7.

Goes from nasal bone superiorly to skin of forehead between the eyebrows.

Pulls skin between eyes down during frowning.

Question 18

Depressor septi nasi

Answer 18

CN7

Originates in maxilla, inserts into nasal septum

Pulls nose inferiorly, widens nares

Question 19

Depressor anguli oris

Answer 19

CN7

Inf margin of mandible–> corner of lip

Depresses corner of mouth (frowning)

Question 20

Depressor labii inferioris

Answer 20

CN7

Lateral inf mandible –> center of lower lip

Depresses lower lip laterally.

Question 21

Mentalis

Answer 21

CN7

Med inf mandible –> lower lip

Positions lip when drinking from a cup or pouting.

Question 22

Risorius

Answer 22

CN7

Lat mandible –> corner of lip

Stretches lips laterally, grin.

Question 23

Zygomaticus major/minor

Answer 23

CN7

Lateral part of zygomatic arch (cheekbone) –> corner of lip

Elevates corners of lip, smile

Question 24

Levator labii superioris

Answer 24

CN7

Medial part of cheekbone to upper lip.

Deepens furrow between nose and mouth (pursing upper lip)

Question 25

Levator labii superioris alaeque nasi

Answer 25

CN7 Lateral nasal bone to upper lip. Flares nostrils.

Question 26

Levator anguli oris

Answer 26

CN7 Upper mouth to corner of lip. Elevates corner of mouth.

Question 27

Orbicularis Oris

Answer 27

CN7 Surrounds mouth Narrows mouth and closes lips.

Question 28

Buccinator

Answer 28

CN7 Posterior maxilla and mandible --> orbicularis oris muscle. Muscular component of cheek. Pressing cheeks against teeth, forcibly expelling air from cheeks.

Question 29

Platysma

Answer 29

CN7 Subcutaneous fascia near clavicle --> orbicularis oris Draws corners of mouth inferiorly, widens mouth. Draws skin of neck superiorly when teeth clenched.

Question 30

Occipitofrontalis

Answer 30

CN7 Frontal belly on forehead (skin of eyebrows), Occipital belly on back of head (superior nuchal line, mastoid process of temp bone), epicranial aponeurosis connects 2 bellies by running on top of head (scalp). Wrinkles forehead, moves scalp, raises eyebrows.