BONES- Pt 2

Ossification(osteogenesis)

process of bone tissue formation

what is Endochondral ossification

bone forms by replacing hyaline cartilage

what is Intramembranous ossification

bone develops from fibrous membranes 

Endochondral ossification is associated with..

cartilage

Intramembranous ossification is associated with…

membrane bones

Endochondral ossification forms essentially…

all bones below skull, except clavicles 

Step 4 of endochondral ossification

Diaphysis elongates + medullary cavity forms

what step of endochondral ossification does this occur in?
Secondary ossification centers appear in epiphyses

step 4

what is step 5 of endochondral ossificaiton?

Epiphyses ossify

intramembranous ossification forms…

frontal, parietal, occipital, temporal, and clavicle bones

step 1 of Intramembranous ossification

Ossification centers appear in membrane

step 2 of Intramembranous ossification

osteoid is secreted in membrane and calcifies

step 3 of Intramembranous ossification

woven bone and periosteum form

step 4 of Intramembranous ossification

Lamellar bone replaces woven bone and red marrow appears

Bones increase thickness through which kind of growth?

appositional growth

Interstitial growth requires presence of….

epiphyseal cartilage in the epiphyseal plate

what are the 5 zones of the epiphyseal plate?

resting (quiescent), proliferation (growth), hypertrophic, calcification, ossification (osteogenic)

when do the epiphyseal (growth) plates close in females?

(when bone lengthening ceases)

18 yrs

when do the epiphyseal (growth) plates close in males?

(when bone lengthening ceases)

21 yrs

what is osteomalacia?

when bones are poorly mineralized

Osteomalacia results in….

soft, weak bones and pain upon bearing weight

Osteoporosis (a disease) is when..

bone resorption exceeds deposit

what remains normal in osteoporosis?

bone matrix

men are less prone to osteoporosis due to…

protection from testosterone

what are traditional treatments for osteoporosis?

Calcium, Vitamin D, Weight exercise

what does Bisphosphonates do for osteoporosis?

decrease osteoclast activity and # which reverses osteoporosis in spine

what is Denosumab?

Monoclonal antibody shown to reduce fractures in men w/prostate cancer

Denosumab improves…

bone density in elderly

what can you do to prevent osteoporosis?

weight exercises, reduce of carbonated drinks, calcium

what is Paget’s Disease?

Excessive and haphazard bone deposit and resorption causing bone to be made fast and poorly

a very high ratio of spongy to compact bone, combined with reduced mineralization is associated with what?

Paget’s disease

bone mass decline is associated with what?

osteoporosis

what is the 1st stage of healing in a fracture?

Hematoma formation

what is the 2nd stage of healing in a fracture?

Fibrocartilaginous callus formation

what is the 3rd stage of healing in a fracture?

 Bony callus formation

what is the 4th stage of healing in a fracture?

 Bone remodeling 

what does a nondisplaced fracture mean

ends retain normal position

If there is a large gap between the epiphysis and diaphysis, that indicates the person is

young

in adults, red marrow is found in ______, yellow marrow found in _______

epiphyses; diaphysis

red marrow in babies are found where?

in spongy bone and cavity

In intramembranous ossification, bone replaces…

mesenchymal cells

osteon is

the structural unit for compact bone

What is responsible for high tensile strength, flexibility, and resilience of the bone?

sacrificial bonds

Comminuted fracture

Bone fragments

Spiral fracture

candy cane, twisting

Greenstick fracture

incomplete fracture

Compound fracture

Outside body, skin is penetrated

what does a displaced fracture mean?

Bone fractures are not aligned

Depressed fracture

Pressed inward

Simple fracture

Inside body

Compression fracture

Bone is crushed

What is Wolf’s Law

states that bones grow or remodel in response to demands placed on them

step 1 of Endochondral ossification

Bone collar forms around diaphysis of cartilage

step 2 of Endochondral ossification

Cartilage in diaphysis calcifies and develops cavities

step 3 of Endochondral ossification

periosteal bud invades internal cavities and spongy bone forms

primary ossification centers leads to_____, while secondary ossification centers leads to ______

diaphysis; epiphyses

open reduction in fractures

surgical pins or wires secure ends

closed reduction in fractures

physician manipulates to correct position

endochondral ossification has ___ steps while intramembranous has ___

5; 4

growth hormone

stimulates epiphyseal plate activity in early life

Thyroid hormone

modulates activity of growth hormone

testosterone(males) and estrogen(females)

promotes growth spurt, ends growth by closing epiphyseal plate

Effect of Calcitonin

neg feedback; produced by thyroid in response to high calcium levels; lowers calcium levels

what determines whether and when bone remodeling occurs?

hormonal controls

what determines where bone remodeling occurs?

mechanical stress

what are the 3 classification of fractures and what do they include

position of bone ends (displaced/nondisplaced)
completeness of break (complete, incomplete)
whether skin is penetrated (compound/simple)

in fractures, compound is also ____ and simple is also ___

open; closed

what does a complete fracture mean?

broken all the way through

what does a open (compound) fracture mean?

skin is penetrated, outside body

what does a closed(simple) fracture mean?

skin is not penetrated, inside body

what fracture is this

comminuted

what fracture is this

compression

what fracture is this?

spiral

what fracture is this

displaced

what fracture is this

depressed

what fracture type is this

greenstick fracture-incomplete

?

osteon (haversian system)

?

central(haversian) canal

?

spongy bone

?

compact bone

?

circumferential lamellae

?

volkmanns canal

?

osteocyte

?

lacunae

?

canaliculus

do babies have yellow marrow?

no