LAB7

28

• 8 total bones:
• frontal bone (1)
• parietal bone (2)
• occipital bone (1)
• temporal bone (2)
• sphenoid bone (1)
• ethmoid bone (1)

• 14 total:
• zygomatic bone (2)
• Maxilla (2)
• Palatine bone (2)
• nasal bone (2)
• Lacrimal bone (2)
• Vomer (1)
• Inferior nasal concha (2)
• Mandible (1)

• All paired, 6 total:
• Malleus (2)
• Incus (2)
• Stapes (2)

• 22 total bones (auditory ossicles and hyoid bone not included) 6 are paired, the other 8 are not
• 8 neurocranium
• 14 viscerocranium (face)
• 6 auditory ossicles
• 1 hyoid bond

Neurocranium and viscerocranium - collectively termed the skull

Parietal bone and temporal bone

• zygomatice bone
• maxilla
• palatine bone
• nasal bone
• lacrimal bone
• inferior nasal concha

all of them: Malleus, incus and stapes

hyoid bone, not paired

the dome-like "roof" of the cranial cavity

• the depression on the side of the skull anterior and slightly superior to the ears
• "temples"

a horizontally oriented bony bridge formed btwn the temporal and zygomatic bones located about halfway btwn the eye and the ear

• houses the eyeball
• has 7 osseous components: maxilla, frontal, sphenoid, zygomatic, lacrimal, ethmoid, and palatine bones

• Optic canal of the sphenoid bone: the small medial opening
• Superior orbital fissure: the superior part of the larger, elongated opening
• Inferior orbital fissure: the inferior part of the larger, elongated opening

the large passageway in the occipital bone through which the spinal cord passes

• Left and Right
• the paired neurovascular passageway located in a few millimeters lateral to the anterior limit of the foramen magnum of the occipital and temporal bones

• Left and Right
• The pair of foamina anterior to the foramen magnum (and one cm. on either side of the midline)
• In life these foramina are filled with cartilage and do not transmit any structures of significance

• forms the bony roof of the oral cavity
• composed of parts of the maxillae and the palatine bones

• the largest and deepest of the three fossae
• the foramen magnum is located therein

formed by the sphenoid bone centrally and parts of the temporal bones laterally

formed primarily by the frontal bone with small contributions from the sphenoid and ethmoid bones

• "brain case"
• 8 total including
• parietal bone (2)
• temporal bone (2)
• frontal bone (1)
• occipital bone (1)
• sphenoid bone (1)
• ethmoid bone (1)

that portion of the floor of the neurocranium formed by endochondral ossification

forms the superior limit of the anterior aspect of the orbit

• petrous - houses the inter ear
• tympanic
• squamous parts

stylomastoid foramen of the temporal bone

• left and right
• articular projections on each side of the foramen magnum
• articulate with the atlas

Air-filled diverticuli of the nasal cavity within the body of the sphenoid bone

maxillary nerves

have the cribriform foramina of the ethmoid bone, which fibers of the olfactory nerves pass through to reach the nasal mucosa

• unpaired flat bone, forms the inferior part of the nasal septum
• septum is also partly formed by cartilage and partly by the perpendicular plate of the ethmoid bone
• articulates with the L&R maxilla, L&R palatine bones, sphenoid bone and ethmoid bone

opening under each orbit that transmits the infraorbital nerve and vessels

• "check bone"
• temporal process of the zygomatic bone and the zygomatic process of the temporal bone

the mandible

• serves as a point of attachment for several muscles of the tongue and neck
• is "buried" in skeletal muscle in the upper cervical region

the collective vertebral foramina

• Cervical 7
• Thoracic 12
• Lumbar 5

• hole in each transverse process termed the transverse foramen of a cervical vertebra
• small vertebral bodies

• C1, atypical in several respects:
• the "body" of the atlas is so reduced it's termed the "anterior arch of the atlas"
• The "arch" of the atlas is termed "posterior arch of the atlas" to distinguish it nomenclatrually from it's posterior counterpart
• lateral aspects of the atlas where it's two arches join are the right and left lateral masses of the atlas. penetrated by transverse foramina

• C2
• body has a superior "tooth-like" profection termed the dens of the axis, articulates with the fovea dentis (developmentally, the dens is considered to be part of the body of the the atlas that fuses, instead, to the body of the axis

presence of costal fovea

• 5, bodies are larger than the vertebrae above them (since they carry considerable weight)
• characterized by their well developed transverse processes.
• articular processes are oriented in sagittal planes allowing for more forward/backward bending at the joint

• developmentally, there are usually 5 of them known as S1-S5, although they do fuse together to form one definitive bone know as the bony sacrum (fuse at transverse processes of sacral vertebrae)
• transmits the upper body weight to the inferior limbs through the sacroiliac joints

anterior aspect of the bony sacrum so named because it faces the pelvic cavity

• Anterior = Pelvic surface of the sacral bone
• Posterior = Dorsal surface of the sacral bone

C₂T₁₂L₅S₅C_y5

• the sternum, ribs, costal cartilages, and all 12 PAIRS of ribs
• a total of 37 bones

• 12
• head, neck, and body

the rounded portion which articulates with the costal fovea of the bodies of the vertebrae

• the articular surface of the head is divided into superior and inferior parts by the crest of the head
• *the inferior part of the head typically articulates with the superior
• aspect of the body of the numerically corresponding thoracic vertebra
• *The superior part of the head articulates with the inferior aspect of the vertebra immediately above
• *Heads of ribs 1, 10, 11 and 12 typically articulate only with the thoracic vertebra of the same # (thus, they have undivided articular surfaces)

major portion of a rib beginning at and including the tubercle, costal angle, and costal groove

the articular surface of the costal tubercle articulates with the costal fovea of the transverse processes of thoracic vertebrae

• 11 total, the spaces btwn the ribs
• numbered 1-11
• occupied by intercostal muscles and by an intercostal artery, vein and nerve

• attached on each rib to the anteromedial end of it's body
• ribs 1-7 join the sternum directly, "true ribs"
• ribe 8-10 attach to each other and to that of rib 7 to form the costal arch
• costal cartilages of ribs 11-12 end within the musculature of the body wall. These last two "false ribs" are also called "floating ribs" no contact with the sternum

• the first rib is short, tightly curved, and flattened
• the 11th rib has a very small tubercle
• the 12th rib lacks a tubercle, angle, and groove

• manubrium of the sternum
• body of the sternum
• xiphoid process of the sternum

the opening at the top of the thoracic cage formed by the first vertebra, fist pair of ribs, and the manubrium of the sternum

the larger opening at the bottom of the thoracic cage

• the areas of soft (connective) tissue which separate the thin plates of bone forming the early neurocranium
• 6 total; 2 are paired, 2 are not
• Anterior fontanel, Posterior fontanel, anterolateral (sphenoidal) fontanels, and posterolateral (mastoid) fontanels

• incisions into the thoracic cavity
• may be performed midsternally or intercostally