Fracture biomechanics and classification

Question 1

What are the four forces on a fracture

Answer 1

bending
torsion
compression
tension

Question 2

What kind fo fracture is compression a good thing for?

Answer 2

A well reduced transverse fracture

Question 3

What happens with compression on a oblique fracture?

Answer 3

Shearing

Question 4

What 2 other forces do we see added during bending and where?

Answer 4

Inherently when something bends, one cortices will undergo compression and one cortices will undergo tension

Question 5

What is the neutral axis?

Answer 5

The point in a bending bone that sees no compressive or tensive forces

Question 6

If you fix a broken bone with an IM pin you want it to run where?

Answer 6

Down the neutral axis

Question 7

Torsion is essentially?

Answer 7

Rotation

Question 8

Tensions causes what phenomena?

Answer 8

Distraction

Question 9

Casts and splints are good at neutralizing?

Answer 9

Bending and are ok at torsion

Question 10

Wires are good at neutralizing?

Answer 10

Tension, that is all

Question 11

Intramedullary pins are good at neautralizing?

Answer 11

bending, bad at all other forces

Question 12

Interlocking nails are good at controlling?

Answer 12

All forces

Question 13

External skeletal fixation is good at controlling?

Answer 13

All forces

Question 14

Bone plates are good at controlling?

Answer 14

all forces but are weakest at bending combined with compression

Question 15

2 ways to describe a fracture with soft tissue damage respect

Answer 15

Closed

Open

Question 16

5 ways to describe fractures with regards to cortical disruption

Answer 16

Greenstick
Fissure
Saucer
Complete
Depression

Question 17

Describe a greenstick fracture

Answer 17

cortex doesn’t break all the way through

Question 18

Describe a fissure

Answer 18

Crack only involving one side of the bone

Question 19

4 ways to describe a fracture with respect to geometry

Answer 19

Transverse
Oblique
spiral
Comminuted

Question 20

2 types of oblique fracture

Answer 20

Long

short

Question 21

4 types of comminuted fractures

Answer 21

butterfly
highly comminuted
segmental
multiple

Question 22

What is the name of the property bone has that means faster or higher energy impacts cause sharding

Answer 22

Viscoelastic nature of bone

Question 23

5 ways to describe a fracture with respect to location within a bone

Answer 23

articular
physeal
metaphyseal
diaphyseal
condylar

Question 24

5 ways to describe a fracture with respect to location within a bone

Answer 24

articular
physeal
metaphyseal
diaphyseal
condylar

Question 25

What does a non displaced fracture suggest?

Answer 25

Intact periosteal sleeve

Question 26

Always describe displacement with regards to which bone piece?

Answer 26

Distal fragment

Question 27

4 causes of bone fractures?

Answer 27

Traumatic
Pathologic
Fatigue
Iatrogenic

Question 28

2 types of traumatic forces causing bone fractures

Answer 28

Direct (outside)

indirect (action of animals own muscles)

Question 29

Order of fractures description goes?

Answer 29

open/closed
geometry
Cortical disruption/completeness
location on the bone
displacement