Chapter 8: Axial and Appendicular Skeleton

alveolar processes

"bumps" that contain the teeth

os coxae

(coxal/innominate) 2 in the pelvic girdle; broadest bone in the body; composed of 3 separate bones that fuse

scapula

a broad, flat, triangular bone that forms the shoulder blade

cleft palate

a congenital fissure in the midline of the palate; results when the left and right maxillary and palatine bones fuse imcompletly or do not fuse at all

sternal angle

a horizontal ridge that may be palpated under teh skin, importan landmark in that costal cartilages of the second ribs attach there may be used to count the ribs

external occiital protuberance

a prominence on the posterior aspect of the skull

spine (scapula)

a ridge of bone on the posterior aspect of the scapual

hyoid bone

a slender curved bone located inferior to the skull between the mandible and the larynx; not attached to other bones; u saped bone that lies in the neck b/c mandible and larynx; held inplace by ligaments and muscles; supports and provides muscle attachemtn for msucles that form floor of mouth and tongue; base of tongue attachment

styloid process

a thin projection of bone located aneromedial to the mastoid process serves as an attachment site for several hyoid and tongue muscles

axis

allows us to shake our head no, C2

lateral border

also called the axillary border is closest to the axilla (armpit)

depressions

alveolus, fossa, and sulcus

lordosis

an exaggerated lumbar curvature often called swayback that is observed as a protrusion of the abdomen and buttocks

kyphosis

an exaggerated thoracic curvature that is directed posteriorly producing a hunchback look

size of pelvic arch

angle betwene pelvic bone (anterior adn medial) male pelvis pubic arch < 90 degrees, female pelvis pubic arch is greater than 90 degrees

ramus

angular extension of a bone relative to the rest of the structure

sphenoid fontanel

anteriolateral; located between frontal, parietal, temporal, and sphenoid bones

pubis

anterior medial portion

body (vertebra)

anterior region of each vertebra is thick and cylindrical in shape; the weight-bearing structure of each vertebra

frontal fontanels

anterior; largest diamond-shaped; located between parietal adn frontal bones; closes (ossifies) by 1 and a half years of age

incus

anvil

process

any marked bony prominence; extension of the bone 2 groups: those that fit into joints: condyle, head, those to which muscles attach: epicondyle, spine, trochanter, tuberosity

sutures

are immovable joints that form the boundaries between the cranial bones; dense irregular connective tissue

glenoid cavity

arm socket: a shallow depression that holds the head of the humerus to form the shoulder joint

clavicular notches

articulate the sternum with the left and right clavicles

occiptial condyles

articulate with the first cervical vertebrae of the vebebral column

medial border

aslo called the vertebral border; the edge of the scapula closest to the vertebrae

sternum

aslo referred to as the breastbone is a flat bone that forms the anterior midline of the thoracic wall

ulna

bone of the forearm; on the little finger side

pelvic inlet

boundary that leads into true pelvis

pelvic outlet

boundary that leads out of true pelvis

female pelvis

broad and shallow, basin shaped

false pelvis

broad, shallow space above pelvic inlet; called false pelvis becaue it's actually located in the abdonminal cavity rather than the pelvic cavity

openings and spaces

canal, fissure, foramen, meatus, sinus

frontal sinuses

cavities wihtin frontal bones (above orbits) usually 2, one above each orbit but varies

maxillary sinuses

cavities within teh maxillary bones (below orbits) usually 2 one below each orbit but varies; the largest of the sinuses

sphenoid sinuses

cavities within the sphenoid bone, number varies

sinus

cavity or hollow space in a bone; cavity within bone

clavicle

commonly called the collarbone is an enlongated s-shaped bone that extends between the manubrium of the sternum and the acromion of hte scapula

ethmoid

complex, irregularly shaped bone; general locatoin between nasal and sphenoid bones; where the ethmoid bone can be seen in articulated skull: 1. medial walls of orbits 2. upper portion of nasal septum 3. upper "ledges" projecting into the nasal cavities 4. anterior cranial floor

axial skeleton

composd of the bones along the central axis of the body that are commonly dividied into three regions the skull, vertebral column, and the thoracic cage; creates a framework that supports and protects the organs, spongy bone of this part of the skeleton contains hemopoietic tissue that is responsible for blood cell formation

base (cranium)

composed of portions of the ethmoid, sphenoid, occipital, and temporal bones

infraobrtibal foramen

conducts blood vessels and nerves to the face

articulating surfaces

condyle, facet, head, & trochlea

sagittal suture

connects the left and right parietal bones along the midline of the skull

pectorial girdle

consists of the 2 clavicle bones, and 2 scapula bones

pelvic girdlge

consists of the 2 os coxae bones

projections for tendon and ligament attachment

crest, epicondyle, line, process, ramus, spine, trochanter, tubercle, tuberosity

alveolus

deep pit or socket in the maxillae or mandible

mandibular fossa

depressed area in the temproal bone into which the mandible fits

sella turcia

depression in the center of the spheniod bone, which houses the pituitary gland

secondary curves

develop after birth concave; cervical and lumbar

lumbar curve

develops as child learns to walk

cervical curve

develops as infant learns to hold head erect

cranial cavity

encloses, protects, and supports the brain

laminae

extend posteromedially from teh posterior edge of each pedicle

external auditory meatus

external ear canal, tube that extends into the temporal bone from the external to middle ear

fossa

flattened or shallow depression into which another bone fits

facial bones

form the face; protect the entrance to the digestive and respiratory system ex: zygomatic bones, lacrinal bones, nasal bones, inferior nasal conchae, palatine bones, maxillae, vomer, and mandible

cranial bones

form the rounded cranium; completely surrounds and encloses the brain consists of a roof and a base

acromion

forms the bony tip of the shoulder

frontal bone

forms the forehead

vomer

forms the lower portion of nasal septum

malleus

hammer

acetabulum

hip socket: a deep depression that holds the head of teh femur to form the hip joint

supraorbital foramen (notch)

hole/notch above orbit, have two

superior border

horizontal edge of the scapula superior to the spine of teh scapula

palatine bone

horizontal plate, posterior poriton of the hard palate

sexual dimorphism

human femal and male skulls display some obvious differences in general shape and size

appendicular skeleton

includes the bones of the upper and lower limbs and the girdles of bones that attach the upper and lower limbs to the axial skeleton

fontanelles

infant cranial bones are not yet large enough to surround the brain completly so some cranial bones are interconnected by flexible areas of dense regular connective tissue membrane in regions, also called soft spots; allows for compression of the skull to pass through the birth canal

manubrium

is the widest and most superior portion of the sternum

inferior articular processes

joining processes; one way that the verebrae join together (they are also join by thier body)

symphysis pubis

joint between the pelvic bones (pubis protin) anterior and medial; composed of cartilage (fibrocartilage)

interosseous membrane

keeps the bones a fixed distance apart and allow the bones to pivot about one another

patella

kneecap

femur

large blood supply; thigh bone; longest largest, strongest bone

foramen magnum

large hole, the hole through which the spinal cord enters the cranial cavity

condyle

large, smooth, rounded articulating oval structure; rounded bump that usually fits into a fossa on another bone forming a joint

floating ribs

last two pairs of false ribs they have no connection with the sternum

intervertebral foramina

lateral openings between adjacent vertebrae provide a horizontally directed pasagewya throgh which spinal nerves extend to various parts of the body

transverse processes

lateral projections on both sides of the vertebral arch

orbits

left and right are formed from a complex articulation of multiple skull bones

nasal bones

left and right form the bony bridge of the nose

humerus

long bone of the upper arm; lots of attachment points for muscles

line

low ridge

mandible

lower jaw; very thick bone; largest strongest bone of teh face, only moveable bone of the face

ischium

lowermost portion (strongest)

body

main portion of the bone

trochanter

massive, rough projection found only on the femur; large bump for muscle attachment

scoliosis

most common spinal curvature deformity an abnormal lateral curvature that sometimes results during dvelopment when both teh vertebral arch and bod fail to form or form incompletly on one side of a vertebra

male pelvis

narrow and deep, funnel shaped

sulcus

narrow groove

crest

narrow, prominent, ridgelike projection

fissure

narrow, slitlike opening through a bone

herniated disc

occurs when the gelatinous nucleus pulposus protrudes into or thorugh the anulus fibrosus

pedicles

originate from the posterolateral margins of he body

pelvic girdle

os coxae (2) + sacrum + coccyx; forms complete bony ring

bones of the ear

ossicles, 6 in total tiny bones located within the temporal bones (in middle ear) 3 per ear

canal

passageway through a bone

meatus

passageway through a bone; tubelike canal in bone

mastoid fontanel

posteriolateral; located between parietal, occipital and temporal bones

verebral arch

posterior to the vertebral body also called teh neural arch

occipital fontanel

posterior, located between parietal and occipital bone

primary curves

present from birth convex, thoracic, sacral (pelvic)

epicondyle

projection adjacent to a condyle; for muscle attachment

mastoid process

projection of boen just behind ear; contains mastoid air celsl (small sinuses that communicated with middle ear ratehr than nose)

spinous process

projects posteriorly form the junction of the left and right laminae most of these can be palpated along the skin of the back

head

prominent, grooved, pulley-like articular process; large, rounded distinct end of a long bine that fits into a depression on naother bone forming a joint

costal notches

represents articulations for the first ribs costal cartilages

xiphoid process

represents the very tip of the sternum small inferiorly pointed cartilagionous projection often doesn't ossify until after age 40

true ribs

ribs 1-7 connect individually to the sternum by seperate cartilaginous extensions

false ribs

ribs 8-12 their costal cartilage do not attach directly to the sternum costal cartialge of 8-12 fuse to the costal cartilage of rib 7

foramen

rounded passageway through a bone for blood vessels and nerves

mandibular condyle

rounded portion of mandible that fits into mandibular fossa of temporal bone to form teh jaw joint

coronal suture

runs along the coronal plane; suture between the frontal and parietal bones

intervertebral discs

seperate vertabral bodies, pads of fibrocartilage composed of an outer ring of fibrocartilage called the anulus fibrosus and an inner gelatinous circular region called the nucleus pulposus, shock absorbers

spehnoid

sits at the base of the cranial cavity; forms central portion of cranial floor (shape resembles bat) known as the "keystone of the cranium" b/c the sphenoid bone anchors all the other cranial bones; forms lateral walls of cranium (lies in front of temporal bone) forms lateral walls of orbits

calvaria

skullcap composed of the frontal bone, the parietal bones, and part of the occipital bone

styloid process

slender spike of bone that extends downward from the temporal bone

tuberosity

small bump for muscle attachment

wormian bones

small island of bone located within sutures; highly individula so the number varies

facet

small, flat, shallow articulating surface

tubercle

small, round projection

ethmoid sinuses

small, spongy cavities that lie within the lateral portions of the ethmoid bone

true pelvis

space between pelvic inlet and pelvic outlet; basin portion of pelvis (houses pelvic organs)

spine

spinous process: pointed, slender process, sharp pointed process for muscle attachment

stapes

stirup

suprascapular notch

suprascapular foramen; in the superior borders provides passage for the suprascapulr nerve and blood vessels

mental protuberance

teh prominent chin of teh mandible

vertebral foramen

the body together with the vertebral arch enclose an opening

atlas

the first cervical verebra supports the head through its articulation wiht the occipital condyles of the occipital bone permits us to nod our heads yes

metatarsals

10 bones that form the long portion of the foot

metacarpals

10; bones that form the palm of the hand (knuckles are the heads)

thoracic vertebrae

12 form the superio region of the back, each vetebra articulates laterally with one or two pairs of ribs

tarsals

14 bones that form the heel and the posterior portion of the foot

carpals

16; bones of the anatomical wrist (proximal end of hand)

inferior turbinates (conchae)

2 along the inferiorlateral walls of the nasal cavity, two scroll-shaped bones

fibula

2 bone of the lower leg, the lateral bone in the lower leg

occipital condyles

2 oval shpaed bumps on either side of the foramen magnum, where the skull joins the vertebral column

palatine

2 shaped like 2 L's facing one another 1. horizontal portion of L's forms posterior portion of hard palate 2. vertical portion of L's forms lateral posterior walls of nasal caviteis

tibia

2 takes the weight of your body; medial and more superficial lower leg bone

zygomatic

2, cheekbones; also form lateral walls of orbits

skull

22 bones: 8 cranial bones and 14 facial bones

vertebral column

26 bones: cervical vertebrae, thoracic vertebrae, lumbar vertebrae, sacrum, coccyx

phalanges

28 bones of the fingers 3 in each finger 2 in each thumb

lacrimal

2; forms medial walls of orbits (b/t the maxilary and ethmoid bones); paper thin bones usually broken in real bone skulls

lumbar vertebrae

5; form the inferior concave region of the back

cervical vertebrae

7, atlas c-1, axis c-2; form the bones of the neck; kidney bean shaped odeis and extend inferiorly form teh occipital bone of the skull through the neck to the thorax; support the weight of the head

cleft lip

the incomplete fusion of upper jaw componenets of the dveloping embroy resulting in a split upper lip extending from the mouth to the side of one nosril

body (sternum)

the longest part of teh sternum and forms its bulk individual costal cartilages from ribs 2-7 are attachd to teh body as indented articular costal notches

palatien process

the portion of teh maxillary bone that forms the anterior and most of the hard palate of the roof of teh mouth

zygomatic process

the portion of the temporal bone that joins the zygomatic bone

suprasternal notch

the shallow superior indentation between the clavicular notches

corcoid process

the smaller more anterior projection that is a site for muscle attachement

articular facet

the smooth surface of the articular process

vertebral canal

the stacked verebral foramina collectively; contains the spinal cord

bone markings

the surface features that characterize each bone in the body

lambdoid suture

the suture between the occiptal bone wiht both parietal bones

nasal septum

the thin ridge of bone that divides the nasal cavity into right and left halves

cribiform plate

thin plate (anterior cranial floor) that crista galli sets on; seperates the cranial and nasal cavities; contains numerous holes for branches of the olfactory nerves

auditory ossicles

three tiny ear bones housed within the petrous part of each temporal bone

optic foramen

transmits the optic nerve (vision) from eye to brain

radius

two on the thumb side, bone of the forearm

maxillary

upper jawbones; form the central portions of teh face; (know as the keystone of the face" becasue anchors all the other facial bones ecept for the mandible) also forms 1. floor of orbits 2. anterior portoins (most) of hard palate

perpendicular plate

upper portin of nasl aseptum (nasal septum is the midlin wall in internal nose)

ilium

uppermost flaring portion

crista galli

upward projection of ethmoid bone, lies in anterior cranial floor; point of attachmetn for the meninges (protective coverings for the brain and spinal cord)

notch

v like opening in the bone

zygomatic arch

zygomatic process (temporal bone) + zygomatic bone

coccyx

1, commonly called the tailbone formed from four coccygeal vertebrae

sacrum

1, formed by five sacral vertebrae that fuse into a single bony structure by teh mid to late 20's