Muscles of H&N Flashcards
What are the muscles of the face divided into
Muscles of facial expression
Muscles of mastication
What nerve innervates the muscles of facial expression
Facial nerve/CN VII
What are the functions of orbicularis oculi and what branches innervate it
Palpebral part: gently closes eyelids
Lacrial part: drains tears
Orbital part: tightly closes eyelids
Temporal and zygomatic branches
What is the function of buccinator and what nerve innervates it
Pulls cheek inwards against teeth to prevent accumulation of food in that area -> ensure food remains within oral cavity
Facial nerve
What is the function of orbicularis oris and what innervates it
Its fibres enclose the opening to the oral cavity to purse the lips
Facial nerve
What is the function of occipitofrontalis and what innervates it
Raises eyebrows and wrinkles the forehead
Facial nerve
What nerve innervates the muscles of mastication
Mandibular branch (CN V3) of the trigeminal nerve
Name the muscles of mastication
Masseter
Temporalis
Medial and lateral pterygoids
What is the function of masseter
Elevates the mandible -> closes the mouth
What are the functions of temporalis
Elevates the mandible -> closes the mouth
Retracts the mandible to pull the jaw posterior
What is the functions of the medial pterygoid
Elevates the mandible -> closes the jaw
What are the functions of the lateral pterygoids
Bilaterally acts to protract the mandible and push the jaw forwards
Unilaterlly acts to produce side to side movement
Aids in mandible depression
Name the muscles of the neck
Platysma
Trapezius
Sternocleidomastoid
Scalene muscles
Suprahyoids
Infrahyoids
What are the functions of the platysma and what innervates it
Draws down sides of the mouth and tenses the neck skin
(Muscle of facial expression)
Cervical branch of facial nerve innervates
What are the functions of the sternocleidomastoid and what innervates it
Allows head to laterally rotate and rotates chin in opposite direction
Spinal accessory nerve
