14 - Fractures and Bone Healing Flashcards
What type of fracture is most common
Extremity fractures
Men up to 45 + women over 45
Which fracture is most common before and after 75
Before - Wrist
After - Hip
Difference between open and closed fracture
Open fracture the bone fragments pierce the skin
What are displaced fractures
Pieces move out of their normal anatomical position
Transverse fracture
Looks transverse lol
Usually caused by directly applied force to the fracture site
Spiral or Oblique Fracture
Caused by violence transmitted through limb from a distance
e.g if proximal end is wisting
Crush/compression fracture
Result of compression
Burst fracture
in short bones
e.g vertebrae - from strong direct pressure such as impaction of disk
Example of burst fracture
Jumping from building
Force from legs transmitted into vertebral column - disks push up so vertebra burst
Where are burst fractures most common
Thoracic/Lumbar junction
Avulsion fracture
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)
Fracture dislocation/Subluxation
Fracture involves a joint resulting in misalignment of joint surfaces
Impacted fracture
Bone fragments are impacted (forced/pushed) into each other
can see bleeding on MRI
Comminuted fracture
2 or more bone pieces - they’re fragmented
High energy trauma
Disrupts blood supply
need internal fixation
Stress fracture
Fracture to trabecular network inside the bone (hard to see on x-ray)
What is fatigue fracture
Abnormal stress on the bone resulting in a stress fracture
What is a insufficiency fracture
Normal stress on abnormal bone resulting in a stress fracture
Torus fracture
Common in children
In softer bones - trabecular compression
heals v quickly as woven bone
Greenstick
In children
Bones are soft and bend without fracturing completely
Fractures one side but does not go all the way through
Fractures of the epiphyseal growth plate
May interfere with growth if closes too early
if radius stops growing the ulnar will overgrow to compensate and needs to be cut
Stages of bone healing
1) Fracture hematoma
2) Fibrocartilaginous callus
3) Inflammatory, granulation and soft callus
4) Bony callus
5) Bone remodelling
what occurs in the fracture hematoma stage
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
what occurs at the fibrocartilaginous callus stage
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
what occurs at the Inflammatory, granulation and soft callus stage?
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
What occurs at the bony callus stage
3-4 months
osteoblasts make woven bone
Bone remodelling stage
Osteoclasts remodel woven bone into compact bone and trabecular bone
Often no trace of fracture line on X-ray
