14 - Fractures and Bone Healing

Question 1

What type of fracture is most common

Answer 1

Extremity fractures

Men up to 45 + women over 45

Question 2

Which fracture is most common before and after 75

Answer 2

Before - Wrist

After - Hip

Question 3

Difference between open and closed fracture

Answer 3

Open fracture the bone fragments pierce the skin

Question 4

What are displaced fractures

Answer 4

Pieces move out of their normal anatomical position

Question 5

Transverse fracture

Answer 5

Looks transverse lol

Usually caused by directly applied force to the fracture site

Question 6

Spiral or Oblique Fracture

Answer 6

Caused by violence transmitted through limb from a distance

e.g if proximal end is wisting

Question 7

Crush/compression fracture

Answer 7

Result of compression

Question 8

Burst fracture

Answer 8

in short bones

e.g vertebrae - from strong direct pressure such as impaction of disk

Question 9

Example of burst fracture

Answer 9

Jumping from building

Force from legs transmitted into vertebral column - disks push up so vertebra burst

Question 10

Where are burst fractures most common

Answer 10

Thoracic/Lumbar junction

Question 11

Avulsion fracture

Answer 11

Caused by traction
bony fragment usually torn off by a tendon or ligament where they insert into the bone
Usually a displaced fraction as the attachment point comes off the body of the bone
(internal fixation to repair)

Question 12

Fracture dislocation/Subluxation

Answer 12

Fracture involves a joint resulting in misalignment of joint surfaces

Question 13

Impacted fracture

Answer 13

Bone fragments are impacted (forced/pushed) into each other

can see bleeding on MRI

Question 14

Comminuted fracture

Answer 14

2 or more bone pieces - they’re fragmented
High energy trauma
Disrupts blood supply
need internal fixation

Question 15

Stress fracture

Answer 15

Fracture to trabecular network inside the bone (hard to see on x-ray)

Question 16

What is fatigue fracture

Answer 16

Abnormal stress on the bone resulting in a stress fracture

Question 17

What is a insufficiency fracture

Answer 17

Normal stress on abnormal bone resulting in a stress fracture

Question 18

Torus fracture

Answer 18

Common in children
In softer bones - trabecular compression
heals v quickly as woven bone

Question 19

Greenstick

Answer 19

In children
Bones are soft and bend without fracturing completely
Fractures one side but does not go all the way through

Question 20

Fractures of the epiphyseal growth plate

Answer 20

May interfere with growth if closes too early

if radius stops growing the ulnar will overgrow to compensate and needs to be cut

Question 21

Stages of bone healing

Answer 21

1) Fracture hematoma
2) Fibrocartilaginous callus
3) Inflammatory, granulation and soft callus
4) Bony callus
5) Bone remodelling

Question 22

what occurs in the fracture hematoma stage

Answer 22

As the blood supply is damaged the blood from the broken vessels form a clot
6-8 hours after injury
Swelling + inflammation to dead bone cells at injury site

Question 23

what occurs at the fibrocartilaginous callus stage

Answer 23

New capillaries organise the hematoma into granulation tissue (procallus)
Fibroblasts and osteogenic cells invade procallus
Makes collagen fibres which connect together
Chondroblasts produce fibrocartilage
Lasts 3 weeks

Question 24

what occurs at the Inflammatory, granulation and soft callus stage?

Answer 24

o More cartilaginous than bone (lighter pink)
o Inflammatory cells appear
o Organisation and resorption of clot as new capillaries form
o Fibroblasts enter and differentiate as chondrocytes
o Chondrocytes produce collagen that bridges fracture site cartilage and trabecular bone laid down

Question 25

What occurs at the bony callus stage

Answer 25

3-4 months

osteoblasts make woven bone

Question 26

Bone remodelling stage

Answer 26

Osteoclasts remodel woven bone into compact bone and trabecular bone
Often no trace of fracture line on X-ray