WEEK 9 HEAD AND NECK ANATOMY Flashcards
What are the bones of the neurocranium?
Parietal (x2) Temporal (x2) Frontal Occipital Ehtmoid Spehoid
What are the bones of the viscerocranium?
Nasal (x2) Lacrimal (x2) Inferior nasal concha (x2) Maxilla (x2) Palantine (x2) Zygomatic (x2) Mandible Vomer
What is the splancocranium and what constitutes this?
Derived from pharyngeal arches; cartilage and endochronal bone like in ear ossicles(incus, malleus, stapes), styloid process, hyoid
What lies within the anterior cranial fossa?
Frontal lobe of cerebrum
What lies within the middle cranial fossa?
Temporal lobe of cerebrum
What lies within the posterior cranial fossa?
Cerebellum
Which bones make up the roof of the orbit?
Frontal and Sphenoid bone (lesser wing)
Which bones make up the floor of the orbit?
Zygomatic, palantine, maxilla bones
Which bones make up the medial wall of the orbit?
Lacrimal, maxilla, ethmoid bone
Which bones make up the lateral wall of the orbit?
Frontal bone, sphenoid bone (greater wing), zygomatic bone
Where does the maxillary sinus exit?
Into middle meautus
Where does the frontal sinus exit?
Into the middle meatus (meatus is the space b/w the conchae)
Where does the sphenoidal sinus exit?
Above superior concha
Where does the ethmoid sinus exit?
Into the superior and middle meatus
What is the pathway of air through body?
- Air enters nasopharynx
- Then oropharynx
- Then laryngopharynx
What is the calvaria?
The ‘skullcap’ of the cranium consisting of Frontal, Parietal and Occipital bones
Which bones form the cranial base?
Sphenoidal and temporal
What are the superior and inferior tmeporal lines for?
Muscle attachment for anterior and posterior temporalis muscles
What is an important feature of the sphenoid bone?
Sella turcica- has a large anastomosis (if there is blockage in arteries supplying brain, collateral circualation occurs via arteries to supply brain.
What are the 3 foramina in the sphenoid bone?
Rotundum
Ovalle
Spinosum
What is an important feature of the ethmoid bone?
Crista Galli and cribriform plate. (crista galli means cocks comb)
What does contraction of the pterygoid muscle do?
Elevates the mandible (jaw closing) and moves it forward (protrusion)
Where do the pterygoid muscles attach?
Pterygoid plate
Where does the temporal mandibular joint of the mandible sit?
in the mandibular fossa
What is the function of the occipital condyles in occipital bone?
To articulate with the C1 (atlas) vertebra- superior facets
What does the coronal suture connect?
The frontal with parietal bone
What does the squamous suture connect?
Parietal with temporal bones
What does the lambdoid suture connect?
Parietal bone with occipital
What does the sagittal suture connect?
The right and left parts of the parietal bone
What is the attachment site for the masseter muscle?
Ramus and angle
What is the attachment site for the pterygoid muscle?
Internal angle
What process is reabsorbed if you lose adult teeth?
The alveolar process;houses the tooth
What is the most variable region of the mandible?
Mandibular sympysis as the most stress is placed on this when chewing
When do sutures form?
After the fontanelles have fused
What is the function of fontanelles?
Allow passage through birth canal and post natal growth (anterior and posterior fontanelle)
What is the weakest part of the skull?
Pterion (H shaped suture)
What is the function of the hyoid bone?
Aids with swallowing and speech
- Only bone not to articulate with another bone
- Provides major muscle attachment with muscles of pharynx and of the neck
What vertebral level is the hyoid bone?
C3
Where does the hyoid bone attach?
To the larynx below and pharynx posteriorly
What does the obicularis oculi do?
Closes the eye
What does the occipitofronalis muscle do?
Raises the eyebrows
What does the buccinator and obicularis oris do?
Blows out the cheeks with pout
What does the obcularis oris do?
Just pouts the mouth
What are the major muscles of mastication innervated by?
Mandibular branch of trigeminal nerve. (V3)
What are the jaw closing muscles?
Temporalis, Masseter (attaches on mandible and zygomatic bone) and medial pterygoid
What is the jaw opening muscle?
Lateral pterygoid
Do all the muscles of mastication produce the same force?
NO they all produce different forces to be in dynamic equilibrium.
What does the temporomandibular joint (TMJ) do?
Helps elevation and depression, protrusion, retrusion, lateral deviation
What is lateral deviation?
one condyle will protrude whilst opposite condyle will spin around vertical axis (ispilateral-same side or contralateral opposite sides)
What are the muscles of the pharynx?
Superior constrictor, middle constrictor and inferior constrictor (2 parts)
Where does the superior constrictor attach?
To the oropharynx
Where does the middle constrictor attach?
Laryngopharynx
Where does the inferior constrictor attach?
Laryngopharynx
What does the first part of the inferior constrictor consist of ?
superior component (thyropharyngeus) - oblique fibres that attach to THYROID CARTILAGE (adams apple)
What does the second part of the inferior constricro consist of ?
inferior compartment (circopharyngeus).Has horizontal fibres that attach to cricoid cartilage(cartilage links larynx with trachea)
What are the extrinsic muscles of the pharynx?
Elevators and depressors ; suprahyoid and infrahyoid groups of muscles, and stylopharyngeus muscle
What does the suprahyoid group of muscles consist of?
Mylohydoid
Stylohyoid
Digastric
Geniohyoid (MSdG)
What does the infrahyoid group of muscles consist of?
Omohyoid
Sternohyoid
Thyrohyoid
Sternothyroid (OSTS)
What elevates the larynx?
Suprahyoid and stylopharyngeus muscles
What depresses the larynx?
Infrahyoid muscles