head and neck anatomy ch 4-6 exam

muscular system

• system that includes skeletal muscle tissue

muscle

• body tissue that shortens under neural control, causing soft tissue and bony structures to move

origin

• end of muscle attached to least movable structure

insertion

• end of the muscle attached to more moveable structure

action

• movement accomplished by a muscle when muscle fibers contract

cervical muscles

• sternocleidomastoid

• trapezius

sternocleidomastoid

• paired

• one of the largest and most superficial cervical muscle

• origin : medial part of clavicle, sternum’s superior and lateral surfaces

• insertion : mastoid process of temporal bone and anterior portion of the superior nuchal line of the occipital bone

trapezius muscle

• paired

• superficial to both the lateral and posterior surfaces of the neck

• broad, flat triangular muscle

• responsible for shoulder movements

• origin: external occipital protuberance

• insertion: lateral third of clavicle

muscles of facial expression

• epicranial

  • frontalis

  • occipital belly

• orbicularis oculi

• orbicularis oris

• depressor anguli oris

• mentalis

• platysma

• risorius

• buccinator

• corrugator supercilli

• zygomaticus minor

• zygomaticus major

bells palsy

• causes paralysis or weakness in one side of the face

frontalis facial movement

• raises the eyebrows

epicranial facial movement

• surprise

depressor anguli oris facial expression

pulls corners of the mouth down (frowning)

orbicularis oculi facial expression

• closing eyelid and squinting

• opening and closing the eye

zygomaticus major facial expression

• smiling (draws corners of the mouth up)

orbicularis oris facial expression

• puckers lips

• closing and pursing of lips

• pouting or grimacing

mentalis facial expression

• pouting

• raising chin and protruding lower lip

platysma facial expression

• tenses the neck and responsible for grimacing

• raising neck skin

risorius facial expressions

• grimacing

• stretching lips

corrugator supercilli facial expression

• furrows eyebrows

• (not silly)

• frowning

zygomaticus minor facial expression

• raising upper lip to assist in smiling

zygomaticus major, levator anguli oris, risorius facial expressions

• all of these contract when smiling

orbicularis oris

• oris = mouth

• encircles the mouth

• muscle of facial expression

orbicularis oculi

• oculi = eye

• encircles the eyes

levator labii superioris facial expression

• raising upper lip

levator labii superioris alaeque nasi facial expression

• raising upper lip and dilating nares with sneer

depressor labii inferioris facial expression

• lowering lower lip

corrugator supercilli muscle

• is a muscle of facial expression

• moves the eyebrow down and inward toward the nose and inner eye

  • involved in frowning

• “dont be silly”

epicranial muscle 

• a muscle of facial expression

• used when making a “surprised face”

• this muscle covers part of the skull

• consists of two bellys that are separated by a large spread out scalpal tendon

  • occipital

  • fontal

ocipitalis muscle of epicranial muscle

• retracts the scalp

• located on the occipital lobe

frontalis muscle of epicranial muscle

• elevates eyebrows and wrinkles forehead

• insertion: into skin of eyebrow and root of nose

mentalis muscle

• a muscle of facial expression

• works to protrude the lower lip (pouting)

• raises the skin of the chin

• it is the only elevator of the lower lip and chin

• provides vertical support for the lower lip

buccinator facial expression

• compresses the cheeks during chewing

temporalis muscle

• a fan shaped muscle

• main function is to move the mandible

• originates from the temporal fossa and inserts at the coronoid process of the mandible

• its fibers pass deep to zygomatic arch to attach to mandible

muscles of mastication

• masseter

• temporalis

• medial pterygoid

• lateral pterygoid

• responsible for chewing

• innervated by the mandibular division of trigeminal nerve

• motor fibers that contract these muscle travel in the trigeminal nerve

• MONSTOR TRUCKS MAKE LOUDNESS

lateral pterygoid muscle

• a muscle of mastication

• lies superior to the medial pterygoid muscle

• a thick and short triangular shaped muscle located in the infratemporal fossa of the skull

• superior and inferior heads

• causes the power stroke ( moving side to side)

• bilateral contraction:

  • mainly protrusion of mandible with mandible forward

  • slight depression of mandible during opening of jaws

• unilateral contraction

  • lateral deviation of mandible, shift mandible to contralateral side 

trismus

• patient cannot open their mouth due to dysfunction in lateral pterygoid muscle 

medial pterygoid muscle

• attaches to the mandible and to the medial surface of the lateral pterygoid plate

• bilateral contraction

  • elevation of mandible during closing of jaws

• aids in elevating the mandible while closing the jaw, protruding the mandible, and mastication

masseter muscle

• a muscle of mastication

• attaches to the zygomatic arch

• when contracted it elevates the mandible

• most superficial and is the strongest muscle of mastication

• bilateral contraction:

  • elevation of mandible during closing of jaw

bruxism

• bilateral enlargement of the masseter muscle from trauma (grinding)

• grinding of teeth

• alters facial dimensions

buccinator muscle

• keeps food under molars during chewing

  • compresses cheeks inward during use

• assists the tongue in keeping bolus of food in the center of mouth

hyoid

• the only bone in the body that does not attach to another bone

• small, u-shaped located in the anterior midline of the neck

• geniohyoid

• stylohyoid

• omohyoid

• all attach directly to the hyoid bone

suprahyoid muscles

• purpose is to elevate the hyoid bone

• digastric

• mylohyoid

• stylohyoid

• geniohyoid

infrahyoid muscles

• acts to depress the hyoid bone

• group of four pairs of muscles in the anterior (frontal) part of the neck

• omohyoid

• sternohyoid

• sternothyroid

• thyrohyoid

• recieve motor fibers from the cervical spinal serves

omohyoid

• an infrahyoid muscle

• has 2 bellies that are connected by a tendon

• originates from the scapula and inserts on the hyoid bone

• depresses hyoid bone

extrinsic tongue muscles

• hypoglossus

• genioglossus

• styloglossus

• palatoglossus

• used when changing positions of the tongue

• receive motor innervation from the hypoglossal nerve

• involves with protrusion, retraction, depression, and elevation of the tongue

intrinsic tongue muscles

• superior longitudinal 

• inferior longitudinal 

• transverse muscles

• vertical muscles

• receive motor innervation from hypoglossal nerve

• act to change the shape of the tongue

• also move the tongue while suspending and anchoring the tongue to bony structures 

hypoglossus muscle

• extrinsic tongue muscle

• involved with depression and retraction of tongue

• originates along the whole length of the hyoid bone and inserts into the side of the tongue

genioglossus muscle

• protrudes the tongue anteriorly and deviates the tongue to the opposite side

• attaches to the inferior surface of the tongue and the mandible

• aids in swallowing

styloglossus

• lips lateral edges and retracts the tongue

• attaches the styloid process to the tongue

• retracts and elevates the tongue

palatoglossus 

• extrinsic muscle of the tongue

• elevates the posterior portion of the tongue and depresses the soft palate towards the tongue

• creates the anterior faucial pillar in oral cavity

• involved in both speech and swallowing

• originates int he palatine aponeurosis 

soft palate

• closes off the nasopharynx from the oropharynx during swallowing

• essential in breathing, swallowing, and speech

• palatoglossus

• palatopharyngeus

• levator veli palatini

• tensorveli palatini

• uvula

muscles of soft palate

• palatoglossus

• palatopharyngeus

• levator veli palatini

• tensorveli palatini

• uvula

tensor veli palatini

• goes across the pterygoid hamulus to attach to the soft palate

• tenses the soft palate and assists the levator veli palatini in elevating the palate

  • this prevents entry of food into nasopharynx during swallowing

  • only one not laterally connecting the soft palate to the tongue

muscles of pharynx

• involved in speaking, swallowing, and middle ear function

• nasopharynx, oropharynx, laryngopharynx

• stylopharyngeus muscle

• pharyngeal constrictors

• muscles of soft palate

superior constrictor of the pharynx

• construction of the upper part of the pharynx

• originates from the hamulus of the pterygoid plate, mandible, and pterygomandibular raphe

• facilitates in swallowing by pushing the ball of food inferiorly towards esophagus

• attaches to pterygomandibular raphe

middle constrictor of the pharynx

• attaches to hyoid bone

• pharyngeal constrictor muscles receive motor innervation from vagus nerve

• originates on hyoid bone and stylohyoid ligament

inferior constrictor of pharynx

• aids in swallowing by constricting the wall of the pharynx during swallowing

• attaches the thyroid and cricoid cartilages

• pharyngeal constrictor muscles receive motor innervation from the vagus nerve

• all the constrictor muscles insert into the median pharyngeal raphe

temporomandibular joint

• formed by and articulation between the mandibular condyle and the temporal bones

• the muscles involved are attached to the cranium and the mandible

• allows for the mandible to be elevated and depressed

Joint capsule covers the

area, completely encloses the TMJ

disc separates the

bones

A ligament

is a band of fibrous tissue that connects bones.

The 3 paired ligaments of the TMJ

1. Temporomandibular (major)

2. stylomandibular (minor)

3. sphenomandibular (minor)

Temporomandibular

The major ligament is the __. This prevents excessive retraction or moving backward of the mandible.

the __ movement mainly occurs in the upper synovial cavity.

gliding

the __ movement mainly occurs in the lower synovial cavity.

rotation

is a physiologic rest of the mandible. 2mm to 4mm of space between opposing arches

Freeway space

Subluxation

• is the dislocation of both joints

• occurs when the head of each condyle moves too far anteriorly on the articular eminence.

TMD

• temporomandibular disorder

• joint tenderness, neck/shoulder pain from tension, chronic headaches 

articular disc

• a fibrous structure in the TMJ that functions to separate and provide cushion between the temporal bone and the mandibular condyle

powerstroke of mandible

• moving the jaw from side to side → rotational movement

retraction of mandible

• contraction of the posterior fibers of the temporalis muscle

gliding movement of the TMJ

• condyle and the disc of the articular eminence move the jaw forward and backward

sideways movement of mandible

• independent contraction of lateral pterygoid on one side and independent contraction of posterior fibers of temporalis on the other side

depression of mandible

• achieved by contraction of the anterior suprahyoid muscles following stabilization of the hypoid bone by posterior suprahyoid muscles and the infrahyoid muscles 

sphenomandibular ligament

• not strictly considered part of the TMJ but is located on the medial side of the mandible

stylomandibular ligament

• minor

• runs from the styloid process of the temporal bone to the angle of the mandible

• taut when the mandible is protruded

temporomandibular ligament

• located on the lateral side of each joint and forms the lateral part of the joint capsule

• base is attached to the zygomatic process and lateral to the articular eminence

• apex of ligament is fixed to the lateral side of the neck and mandible

synovial cavity

• upper: gliding

• lower: rotation

vascular system of the head and neck..

• consists of an arterial blood supply

• a capillary network

• venous drainage

anastomosis/anastomoses

• communication of blood vessels with other blood vessels 

arterial plaque

• substance lining arteries mainly consisting of cholesterol

arteriole

• smaller artery branching off artery and connecting with capillary

artery

• carry blood away from the heart

• strong, muscular blood vessels that carry oxygen-rich blood from the heart to the body

• handle a large amount of force and pressure from your blood flow but dont carry a large volume of blood

atherosclerosis

• narrowing and blockage of arteries by fatty arterial plaque

bacteremia 

• bacteria traveling within vascular system 

capillary

• smaller blood vessel branching off an arteriole to supply blood directly to tissue

• transport blood, nutrients, and oxygen to cells in your organs and body systems

• smallest blood vessels in vascular system

carotid pulse

• reliable pulse palpated from common carotid artery

embolus/emboli

• foreign material such as a thrombus traveling in blood to block vessel

hematoma

• bruise resulting when a blood vessel is injured and a small amount of blood escapes into the underlying tissue then clots

hemorrhage

• larges amounts of blood escaping into surrounding tissue without clotting

  • when blood vessel is seriously injured

thombus/thrombi

• forming on inner blood vessel wall

vascular plexus

• large network of blood vessels, usually veins

vein

• blood vessel traveling to the heart carrying blood

• carry oxygen-poor blood 

• hold most of the blood in the body 

venous sinus

• blood-filled space between two layers of tissue

venule

• smaller vein draining capillaries and then joins larger veins

blood vessels

• channels that carry blood throughout body

• form a closed loop: begins and ends at heart

• body composed of about 60,000 miles of blood vessels

• able to carry cancer at a faster rate than lymphatic vessels

arterial blood supply

• major arteries that supply the head and neck

  • common carotid artery

  • subclavian arteries

• different origins depending on the side of the body

• unique for head and neck arteries because most are symmetrical

common carotid artery

• left side of the body: originate directly from aorta

• right side of body: branch off brachiocephalic artery

• branchless and travels along neck in lateral position to trachea and larynx

• travels in carotid sheath deep to SCM

• internal and external

subclavian artery

• left side of body: originate directly from aorta 

• right side of body: branch off brachiocephalic artery