Osteology

functions of the skeleton

1. support

2. protection

3. movement

4. storage

5. hemotopoiesis

6. yellow bone marrow

compact bone

dense and smooth (surrounds spongy bone)

spongy bone

open space

long bones

longer than they are wide

short bones

cube shaped, mostly spongy bone

flat bones

thin, flattened, and curved

irregular bones

do not fit into above category, vertebrae

red bone marrow

makes red blood cells, found in flat bones

yellow bone marrow

stores fat and nutrients

tubercle

small rounded projections

tuberosity

medium size rounded projection

tronchanter

large rounded projection

condyle

knuckle like process

meatus

channel

fossa

pit

foramen

hole

crest

ridge on a bone

sulcus

groove

axial skeleton

bones that form the longitudinal axis of the body

parts of the axial skeleton

skull, bony thorax, vertebral column

cranium and facial bones

bones that form the skull

all sets of bones in the skull are joined by immovable joints except what

the mandible/jawbone

structures of the skull: fibrous elastic tissue

holds bones together in the skull (mostly immovable joints)

fontanelles of the skull

spaces between bones that are open, yet covered by thin tissue

axial portion has

74 bones

vertebral column has

5 sections, 26 bones

what are the sections in the vertebral column

1. 7 cervical vertebrae (C1 atlas, C2 axis)

2. 12 thoracic vertebrae

3. 5 lumbar vertebrae

4. sacrum: 5 fused

5. coccyc: 4 fused (tailbone)

sternum - 3 sections

1. manubrium: upper portion

2. body: main section

3. xiphoid process: cartilage

ribs: 12 pairs, 3 types

1. true: 7 pairs, connected to sternum

2. false: next 3 pairs, connected to cartilage of 7th pair then sternum

3. floating: Last 2 pairs, attached to vertebral column and not sternum

hyoid bone

hareshoe shaped bone attached to tongue

ear

3 bones in each hammer (malleus), anvil (incus), stirrup (stapes)

how many bones in the skull

22 bones

appendicular skeleton

includes the limbs and the girdles which attach the limbs to the axial skeleton

pectoral (shoulder) girdle

collar bones (clavicles) and shoulder blades (scapulae)

upper limbs

arms and hands

pelvic (hip) girdle

coxal bones

lower limbs

legs and feet

pectoral girdle

clavicle and scapula

upper limbs

humerus, ulna, radius, carpals, metacarpals, phalanges

pelvic girdle

ilium ischium and pubis

lower limbs

femur, patella, tibia, fibula, tarsals, metatarsals, phalanges

how many bones in the appendicular portion of the body

126 → 64 in arms and 62 in legs

upper limb of appendicular skeleton

humerus, radius, ulna, carpals, metacarpals, phalanges

lower limb of appendicular skeleton

femur, tibia, fibula, tarsals, metacarpals, phalanges

humerus

upper arm

radius

lower; elbow to thumb side of the wrist

ulna

lower arm; elbow to pinkie side of the wrist

pelvic girdle

consists of two coxal or hip bones

what forms each hip bone through fusion

ilium, pischium, and pubis

femur

thigh bone

patella

kneecap

tibia/shin

large bone in lower leg

fibula/lateral ankle

smaller bone in lower leg

diaphysis of long bone

shaft of the bone; composed of compact bone

epiphysis

end of the bone; composed of mostly spongy bone

articular cartilages

cover epiphyses for smooth movement

epiphyseal plate/line

growth plate/marking left from growth at epiphyseal plate

periosteum

fibrous, connective tissue that covers the diaphysis

cancellous/spongy bone

the first bone formed with many spaces in the matrix

compact bone

hard, durable bone we are used to seeing

ossification

the formation of bone from cartilage

intramembranous

fontanelles (membranes) serve as the precursor to bone

first part of endochondrial ossification

blood vessels enter the periosteum (membrane)

second part of endochondrial ossification

osteoblasts move to the entrance

third part of endochondrial ossification

hyaline cartilage cells hypertrophy and die

fourth part of endochondrial ossification

osteoblasts lay down bone in columns called trabeculae

fifth part of endochondrial ossification

cancellous (spongy) bone forms first

sixth part of endochondrial ossification

osteoblasts lay down bone in rings called lamellae

seventh part of endochondrial ossification

projection are shot out and bone solidifies around them leaving cannels or canaliculi leading to the haversian canal

eighth part of endochondrial ossification

osteoblast is now called an osteocyte

osteon

basic unit of bone that contains a central ring, haversian canal, canaliculi, and bone cells

functional joints and amount of movement

fibrous (immovable), cartilaginous (slightly movable), and synovial (freely movable)

structural joints and type of tissue found

fibrous (fibrous connective tissue), cartilaginous (cartilage), and synovial (synovial membrane)

sutures (fibrous connective tissue)

zipper like where bone has fused (skull)

syndesmosis (fibrous connective tissue)

greater distance than a suture (radius and ulna)

gomphosis (fibrous connective tissue)

peg in socket (teeth)

synchondrosis (cartilaginous)

joined by hyaline cartilage - a joint in which the bones are surrounded by hyaline cartilage

symphysis (cartilaginous)

joined by fibrocartilage - permanent in nature (pubis symphysis)

synovial - freely movable (diarthrosis)

articular cartilage, fibrous articular capsule, joint cavity that contains fluid, and is reinforced by ligaments

ball in socket joint

move in all directions

hinge joint

move in one direction

pivot joint

rotation

plane/gliding joint

slide over each other

saddle joint

two convex structures

condyloid joint

allows for side-to-side movement and back and forth movement

flexion movement

decrease angle between two bones

extension movement

increase angle between two bones

abduction movement

moving away from the main axis of the body

adduction

moving toward the main axis of the body

inversion movement

to turn inward

eversion movement

to turn outward

supinate movement

to roll outward

pronate

to roll inward

arthritis

over 20 types - swollen, stiff joints and painful movements caused by mechanical injury, broken bones, bad shoes, and genetics

osteoarthritis

articular cartilage wears away and bones rub over each other and get spurs

rheumatoid arthritis

autoimmune disorder where abnormal pannus tissue forms at joints and bones fuse that shouldn’t inhibit movement

gout

most common in males under 30 and can run in families - uric acid accumulates in the blood and is deposited in joints causing painful movement

scoliosis

lateral curvature of the spine usually in the thoraic region → caused by genetics, polio, and weak muscles

spina bifida

congenital disorder where the lamina of the vertebrae do not fuse making bones unable to support weight