O & I: Face and Neck Muscles Flashcards
Origin: Risorius
Parotid fascia & Buccal skin (highly variable)
Insertion: Risoruis
Angle of mouth (modiolus)
Action: Risorius
part of dilator of mouth; depresses labial commissure bilaterally to frown (sadness)
Origin: Zygomaticus Major
Lateral aspect of zygomatic bone
Insertion: Zygomaticus Major
Angle of mouth (modiolus)
Action: Zygomaticus Major
part of dilators of mouth; elevate labial commissure —
bilaterally to smile (happiness)
Unilaterally to sneer (disdain)
Origin: Mentalis
body of mandible (anterior to roots of inferior incisors)
Insertion: Mentalis
skin of chin (mentolabial sulcus)
Action: Mentalis
elevates and protrudes lower lip; elevates skin of chin (showing doubt)
Origin: Depressor labii inferioris
platysma and anterolateral body of mandible
Insertion: Depressor Labii Inferioris
skin of lower lip
Action: Depressor Labii Inferioris
part of dilators of mouth; retracts (depresses) and/or everts lower lip (pouting, sadness)
Origin: Depressor Anguli Oris
infra-orbital maxilla (canine fossa)
Insertion: Depressor Anguli Oris
Angle of mouth (modiolus)
Action: Depressor Anguli Oris
Part of dilators of mouth; widens oral fissure, as when grinning or grimacing
Origin: Buccinator
mandible, alveolar process of maxilla, and alveolar part of mandible, pterygomandibular raphe
Insertion: Buccinator
angle of mouth (modiolus); orbicularis oris
Action: Buccinator
presses cheek against molar teeth; works /c tongue to keep food btw occlusal surfaces and out of oral vestibule; resists distention (when blowing)
Origin: Temporalis
triangular muscle /c broad attachment to floor of temporal fossa & deep surface of temporal fascia
Insertion: Temporalis
narrow attachment to tip and medial surface of coronoid process and anterior border of ramps of mandible
Innervation: Temporalis
anterior trunk of mandibular nerve (CN V3) via deep temporal branches
Action: Temporalis
elevates mandible, closing jaws; posterior, more horizontal fibers are primary retractors of mandible
Origin: Sternohyoid
manubrium of sternum
Insertion: Sternohyoid
hyoid bone
Innervation: Sternohyoid
ansa cervicali from cervical plexus (C1-C3)
Action: Sternohyoid
fixes or depresses hyoid bone
Origin: Omohyoid
scapula
Insertion: omohyoid
hyoid bone
Innervation: Omohyoid
ansa cervicali from cervical plexus (C1-C3)
Action: Omohyoid
fixes or depresses hyoid bone
Origin: Thyrohyoid
Thyroid cartilage
Insertion: Thyrohyoid
hyoid bone
Innervation: Thyrohyoid
C1 (via hypoglossal n. — CN XII)
Action: Thyrohyoid
fixes or depresses hyoid bone
Origin: Sternothyorid
manubrium of sternum
Insertion: Sternothyroid
Thyroid cartilage
Innervation: Sternothyroid
ansa cervicali from cervical plexus (C1-C3)
Action: Sternothyroid
fixes or depresses hyoid bone
Origin: Digastric
base of cranium
Insertion: Digastric
Hyoid bone
Innervation: Digastric
facial and mandibular nerves
Action: Digastric
depresses mandible against resistance when infra hyoid muscles fix to depress hyoid bone
Origin: Mylohyoid
medial body of mandible
Insertion: Mylohyoid
hyoid bone
Innervation: Mylohyoid
Mandibular nerve (CN V3)
Action: Mylohyoid
depresses mandible against resistance when infra hyoid muscles fix to depress hyoid bone
Origin: Masseter
Quadrate muscle attaching to inferior border and medial surface of maxillary process of zygomatic bone and the zygomatic arch
Insertion: Masseter
Angle and lateral surface of ramps of mandible
Innervation: Masseter
Anterior trunk of mandibular nerve (CN V3) via masseteric nerve
Action: Masseter
elevates mandible, closing jaws; superficial fibers make limited contribution to protrusion of mandible
Origin: Longus Capitis
Basilar part of occipital bone
Insertion: Longus Capitis
Anterior tubercles of C3-C6 transverse processes
Innervation: Longus Capitis
Anterior rami of C1-C3 spinal nerves
Action: Longus capitis
flex head
Origin: Longus Colli
Anterior tubercle of C1 vertebra (Atlas); bodies of C1 - C3 and transverse processes of C3 - C6 vertebrae
Insertion: Longus Colli
Bodies of C5 - T3 vertebrae; transverse processes of C3-C5 vertebrae
Innervation: Longus Colli
anterior rami of C2-C6 spinal nerves
Action: Longus Colli
flexes neck /c rotation (torsion) to opposite side if acting unilaterally
Origin: Geniohyoid
inferior mental spine of mandible
Insertion: Geniohyoid
body of hyoid
Innervation: Geniohyoid
C1 via hypoglossal nerve (CN XII)
Action: Geniohyoid
Pulls hyoid anterosuperiorly; shortens floor of mouth; widens pharynx