Axial Skeleton (skull) Flashcards
(95 cards)
What forms roof of cranial cavity?
Calvaria
What forms rostral wall of cranial cavity
Cribriform plate
What does nasal septum do?
Divides nasal cavity into two nasal fossae
What is the nasal aperture?
Rostral bony opening into nasal cavity
What are choanae?
Two bony openings at the caudal end of the hard palate and nasal septum. Lead from nasal cavity to single nasopharynx
What is a paranasal sinus?
Air filled space in facial bones of the skull (btw external and internal layers)
Name horse paranasal sinuses
Maxillary, frontal, conchal, sphenopalatine
Name biggest paranasal sinus in horse and it’s clinical significance
Maxillary
Teeth can project into it causing sinusitis and affecting the brain
Name ox paranasal sinuses
Frontal, maxillary, conchal, sphenoid and palatine, lacrimal
What is the biggest sinus in an ox
Frontal (extends into the horn in horned ruminants)
Compare maxillary sinus in an ox and a horse
Horse maxillary sinus is split into rostral and caudal parts by a bony septum
Ox only have a singular maxillary sinus
Name what is unique to dogs in mandibular ramus
There are 3 processes
1) mandibular symphysis
2) body
3) Ramus
What is present only in horse mandibles and what is its clinical significance
Vascular notch
Palpating of facial artery for pulse
Name joint that connects mandible to skull
Tembromandibular joint (TMJ)
What is the hyoid apparatus
Series of connected bones that suspend tongue and larynx from the skull in intermandibular space
How does hyoid apparatus differ in horses/ox vs carnivores?
Horses have lingual process-projection of basihyoid bone into the tongue
Ox have this as well but is shorter
Absent in carnivores
Also side of articulation differs in carnivores vs horse/ox
Epihyoid is small in equine
What is zygomatic arch and its clinical significance?
Arch of bone projecting lateral from the skull (widest part of skull)
Forms bridge btw facial and neurocranial regions
Clinically palpable structure
What bones form the zygomatic arch
Zygomatic process of the:
Zygomatic bone
Temporal bone
Maxilla bone
Frontal bone
Why is facial crest (found only in horses) clinically significant
Landmark for maxillary sinus (ventral boundary clinically)
Also can use to find infraorbituve nerve with nasoincisive notch
Ruminants have ___ instead of facial crest
Facial tuberosity
What is the orbit?
Funnel shaped region that houses the eye
How does orbital rim differ btw species
Carnivores - incomplete (orbital ligament closes caudal side)
Horses/ruminants- complete
What is the pterygopalatine fossa?
Depression caudoventral and continuous to the orbit (perioribita fascia separates it in real life) and medial to zygomatic arch/ ramus of mandible. Contains many foramina for vessels and nerves, filled by the pterygoid muscles