Bone Physiology

Question 1

functions of bone

Answer 1

-supports body
-muscle attachment zone
-protects soft tissue
-product blood

Question 2

hematopoiesis

Answer 2

producing blood cells in red bone marrow

Question 3

epiphyseal line

Answer 3

the line given in a long bone after the epiphyseal plate has died (no more bone growth)

Question 4

periosteum

Answer 4

the bone’s ‘skin’

Question 5

bone types

Answer 5

-long
-short
-flat
-irregular

Question 6

long bone

Answer 6

• longer than they are wide
• long shaft with two bulky ends or extremities
  -primarily compact bone but may have a large amount of spongy bone at the ends or extremities
• produce least amount of blood

Question 7

short bone

Answer 7

-roughly cube shaped with vertical and horizontal dimensions approximately equal proportions
-primarily spongy bone covered by a thin layer of compact bone.
-include the bones of the wrist and ankle
-produce most blood

Question 8

flat bone

Answer 8

-thin, flattened, and usually curved
-no bone marrow
-no internal cavity(ies)

Question 9

irregular bone

Answer 9

-bones not characteristic of any other of the bones types (no long, flat, or short)
-primarily spongy bone that is covered with a thin layer of compact bone
-vary in structure and shape

Question 10

what is the bone matrix made out of

Answer 10

-15% H2O, 30% collogen, 55% mineral salts
-Ca(PO4) and Ca(CO3)

Question 11

why is Vitamin D so important for bones?

Answer 11

No Vitamin D = no Ca intake = no Ca for osteoblast = weak bones (less density)

Question 12

lamellae

Answer 12

makes up osteons

Question 13

concentric lamella

Answer 13

lamellae that make up the circle of the osteon

Question 14

interstitual lamellae

Answer 14

lamellae that make up the ‘inbetween’ of the osteons

Question 15

haversion canal

Answer 15

systems of blood vessels that travel through the bones

Question 16

canlicula

Answer 16

where osteocytes ‘reach out’ to communicate with one another

Question 17

bone cells

Answer 17

-osteoblasts
-osteoclasts
-osteocytes
-osteogenic cells

Question 18

osteoblasts

Answer 18

-build bone cells
-become osteocytes with age

Question 19

osteoclasts

Answer 19

-remove/reabsorb bone
-old white blood cells

Question 20

osteocytes

Answer 20

-manage all other bone cells
-old osteoblasts

Question 21

osteogenic cells

Answer 21

-‘baby’ bone cells
-become osteoblasts with age

Question 22

types of fractures

Answer 22

simple
compound
compression
depression
comminuted
impact
spiral
greenstick

Question 23

simple fracture

Answer 23

-only bone damaged
-little to no soft tissue damage
-complete break
-typically transverse

Question 24

compound fracture

Answer 24

-fracture off axis
-open = through skin
-closed = not through skin

Question 25

compression fracture

Answer 25

-crushing/crumbling of bone -common in vertebrae

Question 26

depression fracture

Answer 26

-crushing/indent/pushing force on bone -common in the skull (cranium)

Question 27

comminuted fracture

Answer 27

-3+ fragments of bone broken off -requires hardware to heal correctly

Question 28

impact fracture

Answer 28

-bones crush against one another -think FOOSH

Question 29

spiral fracture

Answer 29

-break caused by twisting force -typically requires hardware to heal correctly -oblique break

Question 30

greenstick fracture

Answer 30

-incomplete fracture of immature bone -only one side of bone broken -IMMATURE BONE

Question 31

steps of bone repair

Answer 31

1) hematoma formation 2) fibrocartilaginous callus formation (aka soft callus formation) 3) bony callus formation 4) bone remodeling

Question 32

hematoma formation

Answer 32

-1st step in bone repair -blood clot formed by broken blood vessels in the bone -6-8 hrs after injury -inflammation occurs

Question 33

fibrocartilaginous callus formation

Answer 33

-2nd step in bone repair -days after fracture occurs -osteoblasts fixes the spongy bone -fibroblast connect broken bones ends -phagocytic cels clean away dead cells

Question 34

bony callus formation

Answer 34

-3rd step in bone repair -usually within week(s) after break -bone 'union' occurs 6-8 weeks later -new bone forms soft callus and then converts to a hard (bony) callus

Question 35

bone remodeling

Answer 35

-4th step in bone repair -8-10 years after break occurs -bone is entirely replaced with new cells (like the fracture never happened)