Axial skeleton - skull

Function of the Axial Skeleton

• Supports and protects body organs – brain; heart;
  lungs
  
  

• Protects special sense organs – eyes; nerves for
  smell; auditory and balance structures
  
  

• Attachment sites for muscles – back muscles;
  intercostal muscles for breathing; facial expressive
  muscles

Face structure

14 bones in total

• All paired except vomer and mandible

What bones in the face are paired? (2 of each)

• Maxillae

• Palatine bones

• Nasal bones

• Inferior nasal conchae

• Zygomatic bones

• Lacrimal bones

Cranium structure

8 bones in total

• Only the parietal and temporal bones are paired

What bones in the cranium are unpaired? (1 only)

• Occipital bone

• Frontal bone

• Sphenoid

• Ethmoid

Associated bones

• 3 pairs of auditory ossicles

• Hyoid is unpaired

What is this view of the adult skull?

Posterior view

What is this view of the adult skull?

Superior view

What joint category do the skull sutures
fall into? Would there be movement at
these joints?

Synarthrotic joints. No, there is no
movement.

Should you try to memorize every feature on the skull?

No; only the features Rudy talks about or that have boxes around them

What view of the skull is this, and what features SHOULD YOU KNOW?

Inferior view with mandible removed

• Palatine process of Maxilla

• Maxilla + Palatine bone

• Zygomatic arch

• Foramen magnum

What view of the skull is this, and what features SHOULD YOU KNOW?

Lateral view

• External occipital protuberance (bump on back of head)

• Temporal process
  of zygomatic bone

• Zygomatic process
  of temporal bone

What view of the skull is this, and what features SHOULD YOU KNOW?

Anterior view

• Components of bony nasal septum - (Vomer + Perpendicular plate of ethmoid)

What view of the skull is this, and what features SHOULD YOU KNOW?

Superior view

• Cribiform plate (Olifactory nerves sit)

• Sella turcica (Pituitary gland sits)

What would sit under the bone here?

Eyeballs + muscles surrounding them

What bone is this?

Sphenoid

What bone is this?

Ethmoid

Palatine bones

• Two bones making up part of the roof of the mouth

• Posterior to the palatine process of the maxilla

Nasal bones

The two nasal bones articulate with the frontal
bone

Inferior nasal conchae

One on each side of the nasal septum attached to
the lateral wall of the nasal cavity

Zygomatic bones

Articulate with the zygomatic process of the
temporal bone.

• Form the zygomatic arch

• Zygomaticofacial foramen

Lacrimal bones

• Found in the medial portion of the orbit of the eye

• Lacrimal groove leads to the nasolacrimal canal

Vomer

• Forms the inferior portion of the nasal septum

What part of the mandible is this?

Superior + lateral surfaces

What part of the mandible is this?

Medial surface of the right half

With which bone does the mandible
articulate / join?

Temporal bone (TMJ = temporo-mandibular joint)

What are the orbits formed from?

• Function is to protect eyes

• Frontal bone makes the roof of the orbit

• Maxilla bone forms the floor of the orbit

• Lacrimal and ethmoid form the medial wall of the
  orbit

• Sphenoid bone forms the posterior wall of the orbit

• Zygomatic bone forms the lateral wall of the orbit

What do the orbits consist of?

Lacrimal gland/adipose tissue/muscles that move
the eye/blood vessels/nerves

Detailed illustration of right eye

Nasal complex

• Anterior nostrils

• Posterior nasal apertures
  
  

• Nasal septum
  • Vomer
  • Perpendicular plate of the ethmoid
  
  

• Nasal wall
  • Nasal conchae

• The Paranasal Sinuses
  • Air-filled chambers that open into the nasal cavity.
  • Frontal sinuses
  • Sphenoidal sinuses
  • Maxillary sinuses
  • Ethmoid air cells

What category of bone do Paranasal sinuses fall into
knowing they have hollow spaces in
them?

Pneumatized bones

Illustration of the paranasal sinuses

Connect to nasal passages

Do the paranasal sinuses lie in the same coronal plane?

Hyoid bone

Suspended by the stylohyoid ligaments
• Does not articulate with any bones and is
therefore extremely mobile

Consists of:
• Greater and lesser horns
• Serve as points for muscle and ligament
attachments