A4: Physeal fractures

Question 1

What happens at the epiphysis?

Answer 1

Articular cartilage and bone elongation

Question 2

What happens at the apophysis?

Answer 2

Ligament or tendon insertion, non-articular, bone elongation

Question 3

What is the blood supply to the epiphyses?

Answer 3

Epiphyseal artery, metaphyseal artery (through perichondral arterioles)

Question 4

Which screw types do you use to fix growth plate fractures?

Answer 4

Smooth pins or lag screws

Question 5

Which Salter Harris types are intra-articular?

Answer 5

III and IV

Question 6

What % of fractures in growing dogs include the growth plate?

Answer 6

30% - as weakest point

Question 7

Why do most fractures occur through the hypertrophic zone?

Answer 7

High matrix to cell ratio

Question 8

What happens if the fracture is somewhere other than the hypertrophic zone?

Answer 8

Causes apoptosis so the growth plates shut down

Question 9

How quickly do growth plate fractures heal?

Answer 9

2-3 weeks

Question 10

How much growth is at the proximal vs distal radius?

Answer 10

40% proximal, 60% distal

Question 11

How much growth is at the olecranon vs distal ulna?

Answer 11

Olecranon 0%, distal 100%