Chapter 11 Cranium Part 1

Cranial Bones Skull = __________ and ________ bones Cranium (8 bones) – Area that surrounds and protects the brain. –____________ (Skull Cap) –Floor

Calvarium __________ Parietal (Right and Left) __________

Frontal Bone ____________ (Vertical) Portion –Forehead ___________ (Horizontal) Portion –Superior Orbits

Frontal Bone Squamous ___________ –Area between eyebrows _____________ Groove –Depression above eyebrows ______________margin –Superior rim of orbit _____________ ridge (Arch) –Ridge beneath eyebrow

Frontal Bone Orbital _____________plate –Superior portion of each orbit _______________ Notch –Separates orbital plate Articulates with 4 cranial bones –Right and left parietals, sphenoid, _________

Parietal Bones Forms the __________calvarium. Articulates with 5 cranial bones –Frontal, occipital, temporal, sphenoid, parietal

Occipital Bone ___________portion of the calvarium. Squamous Portion _______________Protuberance (Inion) –Prominent bump on the back of head.

Occipital ____________Magnum –Hole for spinal cord _______________ condyles –Articulating surface on each side of foramen magnum. Articulates with 6 bones –2 parietals, 2 temporals, sphenoid, ________

Cranial Floor Temporal (Right and Left) __________ Ethmoid

Temporal Bone Lateral aspect of skull. 3 Portions –___________

Temporal Squamous Portion Vertical aspect and very thin. _______________ –Articulates with Zygoma –____________

Temporal Mastoid Portion Posterior to ___________ _____________ Mastoid Tip

Temporal Petrous Portion Houses hearing and equilibrium _______________ –Petrous Ridges _______________Meatus –Opening for the nerves of hearing and equilibrium ________________

Sphenoid Centrally located. Anchors all 7 cranial bones. _______________(Turk’s Saddle) –Houses _______________ –__________sellae – Posterior wall of sella –_____ – Depression posterior to dorsum sella. –Posterior clinoid –Anterior clinoid

Sphenoid ___________ Wings –Anterior clinoid ___________ Wings –Forms portion of floor and walls of cranium

Sphenoid Lateral ______________ –Lateral downward projections Medial ________________ –Medial downward projections ___________ hamuli –Process off of medial pterygoid

Sphenoid Foramen Foramen ____________

Sphenoid Optic Components Optic __________ (Chiasm) –Groove between Anterior body and lesser wings Optic ___________ –Hole between anterior body and lesser wings Superior ______________ –Space lateral to optic foramen between lesser and greater wings

Ethmoid Bone Small bone lying primarily below floor of cranium. Articulates with 2 cranial bones. ____________ –Horizontal portion ____________ –Superior projection from cribriform plate into frontal bone

More Ethmoid _________________ plate –Downward projection forms nasal septum Lateral _____________ (masses) –Suspend from cribiform Nasal ___________(Turbinates) –Downward projection from labyrinth

Sutures Areas of cranial fusion –Synarthrodial __________ suture –Fuses Parietal to Frontal bone ___________suture –Fuses right and left Parietal __________suture –Fuses Parietal to Occipital __________ suture –Fuses Parietal to Temporal

Fontanels Membrane area as a Child Anterior Posterior Sphenoid (2) Mastoid (2)

Suture Articulations Adult ____________ –Frontal and parietals ____________ –Occipital and parietals ___________ Rt/Lt –GW of sphenoid, temporal, parietal, frontal ___________ Rt/Lt –Temporal, occipital, parietal