Muscles Test

Head & Neck Anatomy Dr. Shean

Oct 21, 2011

Muscles of Facial Expression

• Origin of most is on bones• Innervation of all from CN VII Facial– Exits skull via stylomastoid foramen

Sternocleidomastoid

Sternocleidomastoid

Sternocleidomastoid

Trapezius

Trapezius

Trapezius

Trapezius

Frontalis

Frontalis

Orbicularis Oculi

Orbicularis Oculi

Zygomaticus Major

Zygomaticus Major

Insertion of Zygomaticus Major• Origin: Zygomatic bone• Insertion: blends with muscles

at the angle of the mouth• Action: Elevation of corner of

mouth (smile)

Zygomaticus Minor

Origin of Zygomaticus Minor• Origin: Zygomatic Bone• Insertion: Blends with orbicularis oris

muscle• Action: Elevation of upper lip, produce

nasolabial furrow

Levator Anguli Oris

Levator Anguli Oris

Origin of Levator Anguli Oris• Origin: Maxilla• Insertion: Blends with muscles at angle of

mouth.• Action: Elevation of angle of mouth

(smile).

Risorius

Risorius

Levator Labii Superioris

Levator Labii Superioris alaeque nasi

Levator Labii Superioris

Origin Levator Labii Superioris• Origin: Zygomatic bone, Maxilla• Insertion: Blends with muscles of upper lip• Action: Elevates upper lip (sneer)

Levator Labii Superioris alaeque nasi

Levator Labii Superioris alaeque nasi

Origin of Levator Labii Superioris alaeque nasi

• Origin: Maxilla• Insertion: Alar cartilage of nose, blends with

muscles of upper lip• Action: Elevation of upper lip, dilation of nostril

Orbicularis Oris

Orbicularis Oris

Depressor Anguli Oris

Depressor Anguli Oris

Origin of Depressor Anguli Oris• Origin: Mandible (body)• Insertion: Blends with muscles at

angle of the mouth• Action: Depression of angle of the

mouth (grimace)

Depressor Labii Inferioris

Depressor Labii Inferioris

Origin of Depressor Labii Inferioris• Origin: Mandible (body)• Insertion: Blends with muscles of lower

lip• Action: Depression of lower lip (pout)

Mentalis

Origin of Mentalis• Origin: Mandible• Insertion: Skin of chin• Action: Wrinkles skin of chin, raises and

protrudes upper lip

Buccinator

Buccinator

Origin of Buccinator• Origin: Pterygomandicular Raphe,

Maxilla (lateral aspect), Mandible (lateral body)

• Insertion: Blends with muscles at angle of mouth

• Action: Compression of cheek (inflating a balloon, playing a wind musical instrument)

• Innervation: CN VII Facial Nerve

Platysma

Platysma

Insertion of Platysma• Origin: Fascia of Thorax & upper neck• Insertion: Mandible (lower border), skin &

fascia of lower face, blends with muscles of lower lip & angle of mouth.

• Action: Elevates & creases skin of neck (look of “horror”), depression of lower lip & angle of mouth

Muscles of Mastication

• All work on TMJ• Mandibular movements =

elevation/depression, protrusion/retraction, lateral deviation

• All innervated by CN V (3rd branch) : Mandibular branch of the Trigeminal Nerve

Masseter

Origin of Masseter• Origin: Zygomatic Arch• Insertion: Mandible (External surface of

Angle & Ramus)• Action: Elevation of Mandible (closing

mouth)

Insertion of Massetter• Origin: Zygomatic Arch• Insertion: Mandible (External

surface of Angle & Ramus)• Action: Elevation of Mandible

(closing mouth)

Temporalis

Origin of Temporalis• Origin: Temporal Fossa• Insertion: Mandible (Coronoid process &

Ramus)• Action: Elevation of Mandible (close

mouth)

Insertion of Temporalis• Origin: Temporal Fossa• Insertion: Mandible (Coronoid process &

Ramus)• Action: Elevation of Mandible (close mouth)

Medial Pterygoid

Origin of Medial Pterygoid • Origin: Sphenoid bone (lateral Pterygoid

plate)• Insertion: Mandible (medial surface of angle

& Ramus)• Action: Elevation of Mandible (closing

mouth)

Origin of Medial Pterygoid • Origin: Sphenoid bone (lateral Pterygoid

plate)• Insertion: Mandible (medial surface of angle

& Ramus)• Action: Elevation of Mandible (closing

mouth)

Origin of Medial Pterygoid • Origin: Sphenoid bone (lateral Pterygoid

plate)• Insertion: Mandible (medial surface of angle

& Ramus)• Action: Elevation of Mandible (closing

mouth)

Insertion of Medial Pterygoid• Origin: Sphenoid bone (lateral Pterygoid

plate)• Insertion: Mandible (medial surface of

angle & Ramus)• Action: Elevation of Mandible (closing

mouth)

Lateral Pterygoid

Origin of Lateral Pterygoid• Origin: Spehoid bone (Greater wing &

lateral Pterygoid plate)• Insertion: Mandible (neck) & Articular disc

of TMJ• Action: Protrusion of Mandible

Origin of Lateral Pterygoid• Origin: Spehoid bone (Greater wing & lateral

Pterygoid plate)• Insertion: Mandible (neck) & Articular disc of

TMJ• Action: Protrusion of Mandible

Insertion of Lateral Pterygoid• Origin: Spehoid bone (Greater wing & lateral

Pterygoid plate)• Insertion: Mandible (neck) & Articular disc of

TMJ• Action: Protrusion of Mandible

• REMEMBER THAT THE LATERAL PTERYGOID HAS 2 HEADS: SUPERIOR & INFERIOR HEAD (SEE NOTES)

Hyoid Muscles

• Origins & insertions can be derived mostly from the names

Mylohyoid• SUPRAHYOID• Origin: Mandible (inner aspect of

body)• Insertion: Hyoid bone• Action: Elevation of floor of

mouth• Innervation: Mylohyoid nerve

(branch of Mandibular branch of Trigeminal Nerve CN V 3rd branch)

Insertion of Mylohyoid• SUPRAHYOID• Origin: Mandible (inner aspect of

body)• Insertion: Hyoid bone• Action: Elevation of floor of

mouth• Innervation: Mylohyoid nerve

(branch of Mandibular branch of Trigeminal Nerve CN V 3rd branch)

Digastric Muscle• SUPRAHYOID• Innervation Ant. Belly:

Mylohyoid Nerve ( branch of Mandibular Branch of Trigeminal Nerve)

• Innervation Posterior Belly: Facial Nerve CN VII

Stylohyoid• SUPRAHYOID• Innervation: Facial Nerve CN VII

Geniohyoid• SUPRAHYOID• Origin: Genial tubercles inside of

mandible (mental region)

Sternohyoid

Omohyoid• Infrahyoid• Muscle has 2 bellies (superior &

inferior) joined by intermediate tendon attached to clavicle by fascia

• Innervation (EX CREDIT): Ventral Rami of C 1-3 spinal nerves (cervical nerves/plexus)

Omohyoid

Sternohyoid• Infrahyoid• Innervation (EX CRED): ventral

rami C 1-3 (Cervical nerves/plexus)

Thyrohyoid• Infrahyoid• Innervation (EX CRED): Ventral

Ramus of C1 Spinal Nerve (Cervical nerves/plexus)

Thryohyoid

Tongue Muscles

• Origins & Insertions mostly obvious from names

• ALL innervated by CN XII Hypoglossal Nerve• Intrinsic vs Extrinsic Tongue Muscles

Intrinsic Tongue Muscles• Longitudinal• Transverse• Vertical

Styloglossus

Genioglossus

Genioglossus

Hyoglossus

Stylopharyngeus• Innervation: Gossopharyngeal CN IX

Superior/Middle/Inferior Pharyngeal Constrictor

• Innervation: Pharyngeal Plexus– VAGUS NERVE??? CN X ???

• Action: Produce a wave of contraction (peristalsis) during swallowing

• Origin: – Pterygomandibular Raphe (Sup.)– Hyoid bone (Mid.)– Thyroid & Cricoid cartilages of Larynx

(Inf.)

• Insertion: Post. Midline Raphe, Base of skull (sup. Constrictor)

Palatoglossus

• Action: Elevates & Arches tongue, depressing soft palate toward tongue

• If you found a good pic besides one out of the book (don’t have a scanner) then feel free to share!

• OR Label this pic right here, I’m not sure which part it is.

Palatopharyngeus• Action: Moves palate posteroinferiorly

& posterior pharyngeal wall anterosuperiorly

Levator veli palatini• Raies soft palate to contact the psoterior

pharyngeal wall

Tensor veli palatini• Tenses & slightly lowers soft palate