H&N Muscles Flashcards
Orbicularis oculi (type of muscle, action, location, innervation)
Muscle of facial expression
Orbital portion shuts eyes tighly, palpebral portion shuts eyes gently
Surrounds the orbit, is just inferior to skin, and just superior to orbital septum
Innervated by zygomatic and temporal branches of facial nerve
Occipitofrontalis (type of muscle, action, location, innervation)
Muscle of facial expression
Is actually two muscle bellies - occipitalis and frontalis
Frontalis elevates eyebrows, wrinkles forehead. Occipitalis retracts (moves back) scalp
Frontalis belly covers majority of scalp, occiptitalis body covers posterior aspects
Innervated by facial nerve
Orbicularis oris (type of muscle, action, location, innervation)
Muscle of facial expression
Brings lips together/purses lips
Surrounds orifice of mouth, muscle makes up majority of lips
Innervated by buccal branch of facial nerve
Buccinator (type of muscle, action, location, innervation)
Muscle of facial expression
Compress cheeks against teeth during mastication
Located in cheek, in area between maxilla and mandible
Innervated by buccal branch of facial nerve
Dilator muscles of lips (eg risorius, zygomaticus muscles, etc) - (type of muscle, action, location, innervation)
Muscles of facial expression
Draws angles of mouth laterally and superiorly (smile)
Found either side of lips
Innervated by facial nerve
Platysma (type of muscle, action, location, innervation)
Muscle of facial expression
Depresses angles of mouth, tenses skin on neck
Present within subcutaneous tissue of neck (superficial cervical fascia), blends in with fascia covering anterior chest wall
Innervated by cervical branch of facial nerve
Masseter (type of muscle, action, location, innervation)
Muscle of mastication
Elevates jaw (closes it). Also protrudes mandible.
In cheek region (lateral region of face, from zygomatic arch to mandible)
Innervated by Vc branch of trigeminal nerve
Temporalis (type of muscle, action, location, innervation)
Muscle of mastication
Elevates jaw (closes it). Also retracts mandible.
In region of temple (side of head, neurocranium)
Innervated by Vc branch of trigeminal nerve
Pterygoids (type of muscle, action, location, innervation)
Muscle of mastication
Medial pterygoid elevates and protrudes mandible. Lateral pterygoid depresses and protrudes mandible
Present in the infratemporal fossa (area below and medial to the zygomatic arch)
Innervated by Vc branch of trigeminal nerve
Sternocleidomastoid (type of muscle, action, location, innervation)
Muscle in neck
Rotates head to opposite side, obliquely rotates head
Both heads run up neck, insert into mastoid process behind ear
Innervated by accessory nerve
Trapezius (type of muscle, action, location, innervation)
Muscle in neck
Abduction beyond 90°, retraction of scapula, elevation of scapula, rotation of scapula, etc
Located in posterior neck and also upper back - large muscle
Innervated by accessory nerve, also some fibres from cervical spinal nerves C3 and C4
Medial rectus (type of muscle, action, location, innervation)
Extraocular muscle
Originates from apex of orbit, inserts into medial aspect of sclera
Adducts eye
Innervated by oculomotor nerve
Lateral rectus (type of muscle, action, location, innervation)
Extraocular muscle
Originates from apex of orbit, inserts into lateral aspect of sclera
Abducts eye
Innervated by abducens nerve
Superior rectus (type of muscle, action, location, innervation)
Extraocular muscle
Originates from apex of orbit, inserts obliquely into anterolateral aspect of eye
Elevates eye
Slightly adducts eye
Slightly intorts eye
When eye is in lateral position, this muscle is the most powerful elevator of eye
Innervated by oculomotor nerve
Inferior rectus (type of muscle, action, location, innervation)
Extraocular muscle
Originates from apex of orbit, inserts obliquely into anteroinferior aspect of eye
Depresses eye
Slightly adducts eye
Slightly extorts eye
When eye is in lateral position, this muscle is the most powerful depressor of eye
Innervated by oculomotor nerve
