Bone growth and fracture healing Flashcards

1
Q

What is a fracture?

A

A break in structural continuity of bone - may be a crack, break, split, crumpling, buckle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is the shorthand sign for a fracture?

A

#

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What can lead to bones failing?

A

High energy transfer in normal bones
Low energy transfer in abnormal bones
Repetitive stress in normal bones

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What abnormalities can reduce the threshold for energy transfer in bones?

A

Osteoperosis
Osteomalacia
Metastatic tumour
etc

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What are the 4 stages of fracture repair?

A

Inflammation
Soft callus
Hard callus
Bone remodelling

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

When does inflammation begin?

A

Immediately after fracture

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What happens in inflammation?

A

Haematoma and fibrin clot
Platelets, neutrophils, macrophages, etc
Osteoprogenitor cell activity
Angiogenesis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What are osteoprogenitor cells and what do they do?

A

They are transformed endothelial cells from the medullary canal or periosteum
They are osteogenic inductors of muscle and soft tissue cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is required for angiogenesis?

A

Oxygen gradient - low

Macrophages

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

When does the soft callus stage begin?

A

When pain and swelling subside

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

When does the soft callus stage last until?

A

Bony fragments are united by cartilage or fibrous tissue

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is the purpose of the soft callus stage?

A

Gives fracture some stability
Angulation can still occur
Continued increase in vascularity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is the hard callus stage?

A

Conversion of cartilage to woven bone

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is the bone remodelling stage?

A

Conversion of woven bone to lamellar bone with reconstruction of medullary canal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

How is instability of a fracture expressed?

A

Magnitude of strain

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What happens if strain is too low?

A

Mechanical induction of tissue differentiation fails

17
Q

What happens if strain is too high?

A

Healing process does not progress to bone formation

18
Q

What is delayed union?

A

Failure to heal in expected time

19
Q

What are risk factors for delayed union?

A
High energy injury
Distraction
Instability
Infection
Steroids
Immune suppresants
Smoking
Warfarin
NSAIDs
Ciprofloxacin
20
Q

What is non-union?

A

Total failure to heal