Anatomy Flashcards
What is the most common type of joint in the skull?
Suture
What are the 3 parts of the skull?
Neurocranium
Visceracranium
Mandible
What is the division between the neuro- and viscera-cranium?
Zygomatic bone
What is the basic structure of a skull bone?
Compact bone encompassing spongey bone
What are the 3 main sutures of the skull?
Sagittal
Coronal
Lambdoid
Where is the sagittal suture?
Between the 2 parietal bones
Where is the coronal suture?
Between the parietal and temporal bone
Where is the lambdoid suture?
Between parietal and occipital bone
What do bones of the facial skeleton give attachment to?
Muscles of tongue, mastication and pharynx
What type of bone are the majority of the facial bones?
Irregular
What are the main bony prominences of the skull?
Occipital proturbance Mastoid process Zygomatic arch Styloid process Occipital condyles
What bone is the mastoid process part of?
Temporal bone
What is the zygomatic arch formed from?
Zygomatic process of temporal bone
Temporal process of zygomatic bone
What is the styloid process a part of?
Temporal bone
What are the 3 fossae of the cranial cavity?
Anterior
Middle
Posterior
What parts of the sphenoid bone form part of the floor of the skull?
Body
Pituitary fossa
Greater wing
Lesser wing
What can be seen on the floor of the skull from the inferior aspect?
Occipital condyles Mastoid process Styloid process Lateral and medial pterygoid plates palatine bone
What do the occipital conduces do?
Articulate with the atlas
How can the styloid and mastoid processes be differentiated?
Styloid- smaller, thinner
Mastoid- bigger, more lateral
What is the largest foramen of the skull?
Foramen magnum
What does the foramen magnum contain?
Medulla and left and right vertebral arteries
What are the orbits?
Sockets for the eyeball
What forms the superior margin of the orbit?
Frontal and sphenoid bones
What forms the inferior margin of the orbit?
Maxilla, palatine and zygomatic bones
What forms the medial border of the orbit?
Ethmoid, lacrimal, sphenoid and maxilla bones
What are the air sinuses?
Air spaces present in some skull bones around the nasal cavity
What is the function of the air sinuses?
Decrease weight of skull
Act as buffer for trauma
Vocal resonance
Produce mucus to moisturise inside of nasal cavity
What are the ear ossicles?
3 small bones in the ear that play a role in hearing
What are the 3 ossicles, from superficial to deep?
Malleus (hammer)
Incus (anvil)
Stapes (stirrup)
Where are the ear ossicles found?
Petrous part of the temporal bone
What is the external ear canal’s “formal” name?
External auditory meatus
Where does the scalp extend to?
Anteriorly to frontal bone
Posteriorly to superior nuchal lines of occipital bone
Laterally to zygomatic arches
What forms the zygomatic arches?
Temporal process of zygomatic bone
Zygomatic process of temporal bone
What are the layers of the scalp?
Skin Connective tissue Aponeurosis Loose connective tissue Pericranium
What gives sensory innervation to the scalp?
Anterior to auricle= branches of trigeminal
Posterior to auricle= Cutaneous branches of C2 and C3
What is the arterial supply to the scalp, from anterior to posterior?
Supratrochlear Supraorbital Zygomaticotemporal Superficial temporal Posterior auricular Occipital
How to lacerating scalp wounds bleed and why?
Profusely as fibrous fascia events vasoconstriction
What is the venous drainage of the scalp?
Facial vein
Retromandibular vein
Internal jugular
Subclavian
What are the emissary veins?
Valveless veins connecting veins draining the scalp with intracranial venous sinuses
What is the clinical importance of emissary veins?
Can spread infection intracranially
What is dipole?
Spongey inner cranial bone
What is the lymphatic drainage of the scalp?
No nodes in scalp, lymph vessels drain away to nodes in the head and neck
What are the muscles of facial expression?
Orbicularis oris
Orbicularic could
Occipitofrontalis
Buccinator
Where do muscles of facial expression lie?
In superficial fascia of head and neck
What is the action of the orbiculares could?
Closes eyelids
What is the innervation of the orbiculares could?
Temporal and zygomatic branches of the facial nerve
What is the structure of the orbiculares orgs?
4 independent quadrants that interlace
What is the action of the orbiculares orgs?
Closes mouth and puckers lips
What is he innervation of the orbiculares orgs?
Buccal branch of facial nerve
What is the structure of the occipitofrontalis?
2 bellies- frontal and occipital- lined by epicranial aponeurosis
What is the action of the occipitofrontalis?
Raises eyebrows and wrinkles forehead
What is the innervation of the occipitofrontalis?
Facial nerve
What is the action of the buccinator?
Compresses cheeks against teeth
What is the innervation of the buccinator?
Buccal branch of facial nerve
What is the course of the facial nerve?
Emerges from the cranial cavity via the stylomastoid foramen
What are the 3 salivary glands?
Parotid
Submandibular
Sublingual
What are the extent and relation of the parotid gland?
Anterior border of SCM Zygomatic arch Angle of mandible Masseter External auditory meatus
What is the course of the parotid gland?
Runs forward, superficial to master, then pierces buccinators to open into the oral cavity opposite 2nd maxillary molar