Muscles of Head and Neck Flashcards
Platysma
O: inferior border of mandible, skin of lower face
I: deltopectoral fascia
Innv: Fascial nerve (CN VII)
Action: draws skin of neck superiorly and corners of mouth inferiorly
Very superficial muscle
Sternocleidomastoid
O: manubrium, medial 1/3 of clavicle
I: mastoid process
Innv: spinal accessory nerve (CN XI)
Unilateral: lateral flexion, contralateral rotation
Bilateral: inferior flexion, superior extension
divides neck into anterior and posterior triangles
Scalene Muscles
Anterior, Middle, Posterior
O: cervical transverse processes
I: 1st rib (ANT, MID) 2nd rib (POST)
Sublcavian artery and brachial plexus pass thru ANT and MID
Longus Coli
O: upper thoracic, lower cervical bodies. middle cervical transv. processes
I: upper cervical vertebral bodies
Innv: cervical ant. rami
flex neck
Longus capitis
O: middle cervical transv. process
I: Occipital
Innv: cervical anterior rami
Action: flex neck, flex atlanto-occipital joint
Muscles of Posterior Triangle
Splenius capitis, levator scapulae, scalenes, inferior belly of omohyoid
Suprahyoid muscles
Stylohyoid, mylohyoid, digastric, geniohyoid
Elevate hyoid bone
Digastric
O: Posterior - mastoid notch
Anterior - digastric fossa
I: intermediate tendon near lesser horn of hyoid
Innv: Ant - CN V3 (mandibular), Post - Facial (CN VII)
Sylohyoid innv
CN VII, facial n.
mylohyoid innv
CN V3, mandibular n.
Geniohyoid innv
C1 ant. ramus via hypoglossal n.
Infrahyoid muscles
Sternohyoid, omohyoid, sternothyroid, thyrohyoid
depress, stabilize hyoid
Innv: C1-C4 anterior rami
Muscles of facial expression
CN VII (facial n.)
Skin Movers, Sphincters of the face
occipitofrontalis (frontalis, occipitalis), orbicularis oculi (palpebral and orbital), zygomaticus major, buccinator, orbicularis oris, levator labbi superioris, lavator labbii superioris alaeque nasi, levator anguli oris, depressor labii inferioris, depressor anguli oris, mentalis
Intrinsic eye muscles
Sphincter pupillae - parasympathetic
Dilator pupillae - sympathetic
Ciliary body
Ciliary muscle - parasympathetic
suspensory ligaments
Levator palpebrae superioris
O: common tendinous ring
Ins: superior tarsal plate
Innv: superior division of CN III, occulomotor
Action: elevate upper eyelid
Superior rectus innv
superior division of CN III
lateral rectus innv
CN VI (abducent)
Inferior rectus
Inferior division of CN III
Medial rectus
Inferior division of CN III
Superior oblique
Trochlear, CN IV
Inferior Oblique
Inferior division of CN III
Medial Rectus Action
Strong ADduction
Lateral Rectus Action
Strong ABduction
Superior Rectus
Strong elevation
Intorsion
Slight adduction
inferior rectus
strong depression
extorsion
slight adduction
superior oblique
strong depression
intorsion
slight abduction
inferior oblique
Strong elevation
extorsion
slight abduction
Temporalis
O: floor of temporal fossa, deep surface of temporal fascia
I: coronoid process
Innv: mandibular n (CN V3)
Action: elevate and retract mandible
Masseter
O: Inferior zygomatic arch
I: lateral surface of ramus and angle of mandible
Action: Elevate, protrude
Innv: mandibular n (CN V3)
Lateral Pterygoid Superior Head
O: infratemporal surface of greater wing of sphenoid
I: Articular disc and capsule of TMJ
Innv: Mandibular n. (CN V3)
Action: protrude mandible and depress chin
Lateral Pterygoid Inferior Head
O:lateral surface of lateral pterygoid plate
I: Pterygoid fovea & capsule of TMJ
Innv: Mandibular n. (CN V3)
Action: protrude mandible and depress chin
Medial pterygoid superior head
O: Maxillary tuberosity
I: medial surface of mandibular ramus
Innv: mandibular n. (CN V3)
Action: Elevate and protrude mandible
Medial pterygoid deep head
O: medial surface of lateral pterygoid plate
I: medial surface of mandibular ramus
Innv: Mandibular n. (CN V3)
Action: elevate and protrude mandible
Cricothyroid
O: External surface of cricoid arch
I: inferior thyroid lamina
Innv: External larygneal n.
Action: Lengthen vocal cords
Posterior Cricoarytenoid
O: Posterior cricoid lamina
I: muscular process of arytenoid
Innv: Inferior laryngeal n. (recurrent laryngeal from vagus)
Action: abducts vocal cords
Lateral cricoarytenoid
O: cricoid arch
I: muscular process of arytenoid
Innv: inferior laryngeal n.
Action: adducts vocal cords
Arytenoids
O: body of arytenoid
I: contralateral arytenoid
Innv: inferior laryngeal n.
Action: adducts arytenoids, vocal cords
Thyroarytenoid
O: Thyroid lamina
I: Body of arytenoid
Innv: inferior laryngeal n.
Action: shorten vocal cords
Vocalis
O: vocal process of arytenoid
I: vocal ligament
Innv: Inferior laryngeal n.
Action: shortal vocal cords
Stapedius
CN VII
Dampens vibration of stapes in rxn to damaging loud sounds
Levator Veli Palatini
O: cartilagenous auditory tube
I: Soft palate
Innv: CN X
Action: Elevate soft palate
Tensor veli palatini
O: pterygoid hamulus
I: soft palate
Innv: CN V3
Action: Tense soft palate
Palatoglossus
O: soft palate
I: lateral side of posterior tongue
Innv: CN X
Action: elevate tongue
Palatopharyngeus
O: Soft palate
I: lateral wall of pharynx
Innv: CN X
Action: elevate pharynx
Muscles of Extrinsic Tongue
Genioglossus, Hypoglossus, palatoglossus, styloglossus
CN XII
Pharyngeal constrictors, names, origins, innv, insertion
Names: Superior, middle, inferior pharyngeal constrictors
O:
Superior - pterygomandibular raphe
Middle: greater horn of hyoid
Inferior: thyroid and cricoid cartilage
Ins: midline pharyngeal raphe
Innv: CN X
Killan’s triangle
weak point in inferior constrictor, pharynx
common site of esophageal diverticulum formation.
Pharyngeal Elevators
Palatopharyngeus, stylopharyngeus, salpingopharyngeus
Innv of pharyngeal elevators
Palatopharyngeus: CN X
Stylopharyngeus: CN IX
Salpingopharyngeus: CN X
muscles of nasopharynx
Torus Tubarius, Levator veli palatini, tensor veli palatini
Oropharynx muscles
Stylopharyngeus, glossopharyngeal
Shortens/loosens vocal cords
thyroarytenoid, vocalis
lengthens/tightens vocal cords
Cricothyroid muscle
abduction of vocal cords
posterior cricoarytenoid
adduction of vocal cords
lateral cricoarytenoid, arytenoids
