bone healing

Question 1

porosity

Answer 1

increased porosity=increased compressive strength
cortical has <15%
cancellous=70%

Question 2

Strength

Answer 2

2% increase in length before failure.

Strongest vs compression than tension. Weakest w shear

Question 3

stiffness cortical vs cancellous

Answer 3

cortical 5-10 x more

Question 4

stages

Answer 4

inflammation 1-3days
regeneration
remodeling 4 mon

Question 5

Breakdown of regeneration phase

Answer 5

Hematoma organization 3-10 days

primary bone callus 6-10 wks (absorbed 2.5-4 months)

Question 6

piexoelectric effect

Answer 6

Compression side:electronegative leading to bone
production
Tension side: electropositive leading to bone
resorption

Question 7

direct healing

Answer 7

primary intention. no callus, no motion

Question 8

indirect osseus repair

Answer 8

callus formation