7/29/2019 006 Bones

http://slidepdf.com/reader/full/006-bones 1/26

7/29/2019 006 Bones

http://slidepdf.com/reader/full/006-bones 2/26

•Support

• Protection

•

Movement• Mineral storage

• Blood cell formation(hemopoiesis)

• Triglyceride storage

7/29/2019 006 Bones

http://slidepdf.com/reader/full/006-bones 3/26

7/29/2019 006 Bones

http://slidepdf.com/reader/full/006-bones 4/26

Distal

epiphysis

Proximal

epiphysis

diaphysis

yellow marrow

epiphyseal line

periosteum

compact bone

spongy bone

Endosteum

hyaline cartilage

Sharpey’s fibers 

7/29/2019 006 Bones

http://slidepdf.com/reader/full/006-bones 5/26

7/29/2019 006 Bones

http://slidepdf.com/reader/full/006-bones 6/26

spongybone

centralcanal

compactbone

Haversiansystem

osteocyte

periosteum

7/29/2019 006 Bones

http://slidepdf.com/reader/full/006-bones 7/26

osteocytes

in lacunae

central

canal

canaliculi

in matrix

7/29/2019 006 Bones

http://slidepdf.com/reader/full/006-bones 8/26

7/29/2019 006 Bones

http://slidepdf.com/reader/full/006-bones 9/26

7/29/2019 006 Bones

http://slidepdf.com/reader/full/006-bones 10/26

275 bones12 weeks (6-9

inches long)

7/29/2019 006 Bones

http://slidepdf.com/reader/full/006-bones 11/26

Fig. 06.13

7/29/2019 006 Bones

http://slidepdf.com/reader/full/006-bones 12/26

cartilage

calcifiedcartilage

bone

epiphyseal

plate

epiphyseal

line

Endochondral Ossification

2o ossification

center 

Fetus: 1st 

2 months

AdultChildhood

Just before

birth

7/29/2019 006 Bones

http://slidepdf.com/reader/full/006-bones 13/26

Fig. 06.08

7/29/2019 006 Bones

http://slidepdf.com/reader/full/006-bones 14/26

• GH from anterior pituitary, which is

regulated by T3 and T4 of the

thyroid

• During puberty- sex hormones:

estrogen and testosterone

Hyposecretion of GH- dwarfism

Hypersecretion of GH- gigantism

7/29/2019 006 Bones

http://slidepdf.com/reader/full/006-bones 15/26

• Parathyroid hormone- stimulates

osteoclasts• Calcitonin- inhibits osteoclasts

Maintains homeostasis

7/29/2019 006 Bones

http://slidepdf.com/reader/full/006-bones 16/26

7/29/2019 006 Bones

http://slidepdf.com/reader/full/006-bones 17/26

Osteoblast

Osteocyte

OsteoclastEats bone

Builds new bone

Mature bone cell

7/29/2019 006 Bones

http://slidepdf.com/reader/full/006-bones 18/26

hematoma callus bony callusbone

remodeling

7/29/2019 006 Bones

http://slidepdf.com/reader/full/006-bones 19/26

Usually treated by realignment

• Simple- closed fracture (8-12 wks to heal)bone breaks cleanly; no penetration

• Compound- bone penetrates through skin

• Comminuted- bone fragments into many

pieces; aged or brittle bones• Compression- bone is crushed

• Depressed- broken bone portion isdepressed inward

• Impacted- broken bone ends are forced intoeach other 

• Spiral- excessive twisting of bone

• Greenstick- bone breaks incompletely

7/29/2019 006 Bones

http://slidepdf.com/reader/full/006-bones 20/26

Oblique Comminuted Spiral Compound

7/29/2019 006 Bones

http://slidepdf.com/reader/full/006-bones 21/26

1. Electrical stimulation of the fracture site:

•

Increases speed and completeness of healing• The e- stimulation inhibits PTH and slow osteoclasts

down from reabsorbing bone

2. Ultrasound treatment:

• Daily treatments reduce healing time of broken bones

by 25-35%3. Free vascular fibular graft technique:

• Transplant fibula in arm

• Gives good blood supply not available in other 

treatments4. Bone substitutes:

• Crushed bone from cadaver- but risk of HIV and

hepatitis

• Sea bone- coral

•  Artificial bone- ceramic

7/29/2019 006 Bones

http://slidepdf.com/reader/full/006-bones 22/26

Osteoporosis- bone reabsorption

outpaces bone deposit; bones

become lighter and fracture easier Factors: 

• age, gender (more in women)

• estrogen and testosterone decrease

• insufficient exercise (or too much)• diet poor in Ca++ and protein

• abnormal vitamin D receptors

• smoking

7/29/2019 006 Bones

http://slidepdf.com/reader/full/006-bones 23/26

29 40 84 92

7/29/2019 006 Bones

http://slidepdf.com/reader/full/006-bones 24/26

7/29/2019 006 Bones

http://slidepdf.com/reader/full/006-bones 25/26

• Rickets- vitamin D deficiency

• Osteomalacia- soft bones, inadequate

mineralization in bones, lack of vitamin D

• Pagets Disease- spotty weakening in the

bones, excessive and abnormal bone

remodeling

• Rheumatoid arthritis- autoimmune

reaction

7/29/2019 006 Bones

http://slidepdf.com/reader/full/006-bones 26/26

INQUIRY

http://www.youtube.com/watch?v=DSHoonPWwXQ

1. What does the secondary site of ossification

produce?

2. What is an epiphyseal line?

3. Provide an example of a flat bone?

4. How does PTH effect bone development?

5. How many bones in the adult skeleton?

6. What does an osteoblast do and where are they

primarily found?