bone

Question 1

what is bone graft?

Answer 1

any material either on it’s own or inconjunction with other materials stimulates bone healing

Question 2

what are the uses of bone graft?

Answer 2

• stimulates bone healing
• fusion
• structural support

Question 3

what are the types of bone graft?

Answer 3

origin:
* autograft
* allograft
* xenograft
* artifical substitutes

preparation
* fresh
* fresh frozen
* freeze dried

Question 4

what are the properties of bone graft?

Answer 4

• osteoconductive - 3D scaphold
• osteoinductive - precursors for bone formation
• osteogeneic - contains bone cells needed

Question 5

what is incorporation

Answer 5

graft invaded and replaced by host bone

Cortical bone:
* slower
* graft bone removed first by osteoclasts
* OB then replace with new bone

Cancellous bone:
* creeping substitution - faster
* removal and laying down of new bone is simultaneous

Question 6

how do you set up a bone bank

Answer 6

1. donor consent - patient or relative
2. Screening - HIV, Hep B/C, Syphillis, CJD, infection and malignancy
3. graft processsing:
   Debridement - remove soft tissues
   Ultrasonic washing
   Ethanol - kill bacteria
   Antibiotics soak
   Irradiation - remove last microbes
   Demineralisation - remove some of it’s proteins to stop an immunogenic response
4. Graft presentation:
   Pay off between biological properties and immunogenicity
   Fresh
   fresh-frozen
   freeze-dried

Question 7

what is the difference between lamellar and woven bone?

Question 8

what is the structure of an osteon?
what is the purpose of the cement line?

Question 9

what is the composition of bone?

Question 10

what is the blood supply to bone?