Axial Skeleton Bones, Skull Bones, Muscles of Head Neck and Trunk

Vertebral column

the spine, formed of a number of individual bones called vertebrae and two composite bones (sacrum and coccyx)

Body of Vertebra

big circular part, is weight bearing

vertebral foramen

canal through which spinal cord passes

pedicle of vertebra

attached to and extends posteriorly on either side of the body

Lamina of vertebra

supporting bone between the spikes of the vertebra

spinous process

Posterior projection of a vertebra...usually points down

Transverse process of vertebra

forms joint with ribs in thoracic region, site for muscle attachment in lumbar region

superior articular process

bony process that extends upward from the vertebral arch of a vertebra that articulates with the superior articular process of the next upper vertebra

inferior articular process

bony process that extends downward from the vertebral arch of a vertebra that articulates with the superior articular process of the next lower vertebra

superior articular facet

the part of the superior articular process that articulates with the superior bone to it

inferior articular process

the part of the inferior articular process that articulates with the inferior bone to it

Intervertebral disks

23 total, disks in the spine

cervical vertebrae

C1-C7, have transverse foreamen, has arteries

transverse foramen

holds arteries in cervical vertebra

Atlas

C1, the first vertebra, fits into C2

transverse ligament

This ligament attaches to the lateral masses of C1 to hold the dens in place

Axis C2

has bump where C1 fits into (shake head)

Dens (odontoid process)

a bony projection that extends upward from the vertebral body where C1 rotates on

Thoracic Vertebrae (T1-T12)

second set of 12 vertebrae; they articulate with the 12 pairs of ribs to form the outward curve of the spine

costal facets of thoracic vertebrae

where head of rib connects

Lumbar Vertebrae (L1-L5)

third set of five larger vertebrae, which forms the inward curve of the spine, lack facets and foreamer

Sacrum (S1-S5)

Shapes the posterior wall of pelvis

Formed from 5 fused vertebrae

Superior surface articulates with L5

Inferiorly articulates with coccyx

anterior sacral foramina

holes on the front of the sacrum

Posterior sacral foramina

holes on back of sacrum

sacral canal

continuation of vertebral canal

sacral hiatus

inferior opening of the sacral canal

ala of sacrum

The wing-like projections on either side of the sacrum.

auricular surface

where pelvic bone articulates with sacrum

superior articular process of sacrum

paired processes that extend upward from the sacrum to articulate (join) with the inferior articular processes from the L5 vertebra

superior articular facet of sacrum

where smooth surface is on process

Coccyx

Tailbone

Sternum

Breastbone

manubrium

upper portion of the sternum

clavicular notch

where sternum connects to clavicles

sternal angle

horizontal ridge across front of sternum where manubrium and body meet

body of sternum

large middle portion of the sternum

costal notches of sternum

indentations on sternum where costal cartilages from the ribs articulate

xiphoid process

lower, narrow portion of the sternum

True ribs (1-7)

Cartilage leads to sternum

false ribs (8-12)

ribs that do not have a direct attachment to the sternum

floating ribs

last two pairs of ribs; do not attach to sternum

head of rib

Articulates with the costal facet of a thoracic vertebral body

superior articular facet of rib

articulates with inferior costal demifacet of the thoracic vertebral body one numeric segment superior

inferior articulating facet of rib

articular surface at bottom of rib

neck of rib

between head and tubercle

tubercle of rib

bump on head (lower) points down

Angle of rib

where rib bends

Costal groove of rib

groove on the inferior side of the rib shaft

hyoid bone

a U-shaped bone in the neck that supports the tongue.

body of hyoid bone

middle of bone

greater cornu/horns of hyoid bone

long projections on back

lesser cornu/horns of hyoid bone

teeth like projections

Cranial Bones

skull bones: ethmoid, frontal, occipital, parietal, sphenoid, and temporal

frontal bone

forehead

supraorbital foramen

opening above each orbit allowing blood vessels and nerves to pass

parietal bones

Bones that form the sides and top of the cranium.

temporal bone

bone that forms parts of the side of the skull and floor of the cranial activity. There is a right and left temporal bone. By the ear

Zygomatic arch of temporal bone

cheek bone

zygomatic process of temporal bone

extension from the temporal bone that forms the posterior portion of the zygomatic arch

mandibular fossa of temporal bone

Articulates with the head of the mandible to form the temporomandibular joint. The mandible (lower jaw) joins with the skull at this site.

External auditory/acoustic meatus of temporal bone

opening in the temporal bone extending to the inner ear

sphenoid bone

forms part of the base of the skull and parts of the floor and sides of the orbit...looks like a butterfly

lesser wing of sphenoid bone

anterior and superior to greater wing on the interior of the skull

optic foramen of sphenoid bone

opening to the optic canal

greater wing of sphenoid bone

posterior and inferior to lesser wing on the interior of the skull, also visible in the posterior orbit and lateral side of the skull

sella turcica of sphenoid bone

houses the pituitary gland

lateral pterygoid plate of sphenoid bone

sharp process that laterally and inferiorly projects from the sphenoid

medial pterygoid plate of sphenoid bone

Location: Sphenoid bone (inferior surface)

Thin plate of bone attached to the pterygoid process, longer and more narrow than lateral pterygoid plat, lower end forms hook-like pterygoid hamulus, lateral surface forms wall of pterygoid fossa, medial surface forms lateral boundary of corresponding posterior nasal aperature

Tendon of tensor veli palatine muscle deflects around the pterygoid hamulus, pterygomandibular raphe is attached to pterygoid hamulus

ethmoid bone

forms part of the posterior portion of the nose, the orbit, and the floor of the cranium

perpendicular plate

forms superior part of nasal septum

Cribiform plate of ethmoid

forms the roof of the nasal cavity and has holes through which axons of the olfactory nerves pass.

crista galli of ethmoid bone

superior projection in the middle of the cribriform plate of the ethmoid bone; providing a point of attachment for the dura mater, helping to secure the brain within the skull

Vomer bone

forms the base for the nasal septum

Maxillary bone (maxilla)

Carries the upper teeth and forms the boundary of three cavities: the roof of the mouth (palate), the floor of the nose, and the floor of the orbits.

infraorbital foramen of maxilla

opening under the orbit that forms a passageway for the infraorbital artery and nerve

palatine process of maxilla

roof of the mouth

palatine bone

either of two irregularly shaped bones that form the back of the hard palate and helps to form the nasal cavity and the floor of the orbits

greater palatine foramen

the largest of three openings located in the posterior region of the hard palate

Zygomatic bone

the arch of bone beneath the eye that forms the prominence of the cheek

zygomatic arch

front part of arch that meets the occipital bone

nasal bone

bridge of nose

lacrimal bone

small fragile bone making up part of the front inner walls of each eye socket and providing room for the passage of the lacrimal ducts

Mandible

lower jaw bone

body of mandible

the horizontal portion of the lower jaw

mental foramen of mandible

one of two holes located on the anterior surface of the mandible. It permits passage of the mental nerve and vessels.

angle of mandible

a bony angle formed by the junction of the posterior edge of the ramus of the mandible and the inferior surface of the body of the mandible; marks widest part of lower 1/3 of face.

ramus of mandible

vertical part of mandible

coronoid process of mandible

flattened upward projection from the anterior margin of the mandibular ramus

condyloid process of mandible

Portion of the mandible that fits into the mandibular fossa and forms the TMJ joint

Mandibular condyles

articulate with mandibular fossae to form temporomandibular joints

mandibular notch

Notch between condyles in mandible

mandibular foramen

hole in back of jaw where novocaine goes

Levator scapulae m.

elevates scapula

(anterior, middle, posterior) scalene muscles

•Work with sternocleidomastoid to flex neck

•Pull cervical vertebrae toward 1st and 2nd ribs (lateral flexion of neck)

•Elevate 1st and 2nd ribs during forced inhalation

Sternocleidomastoid m.

Bilaterally, flexes cervical portion of vertebral column

Unilaterally, rotates head to the side opposite the contracting muscle

Sternohyoid m.

larynx and hyoid depression

Sternothyroid m.

thyroid cartilage and hyoid depression

Digastric m.

open mouth and depress mandible

Mylohyoid m.

hyoid elevation

Frontalis m.

draws scalp anteriorly, raises eyebrows, wrinkles forehead