Traum - Fractures Flashcards
Pathophysiology (part 1):
of a bone break
bleed blood vessels in bone, periosteum
bleeding, inflamm around bone due soft tissue damage
haematoma/clot forms in medullary canal under periosteum
between ends bone fragments
necrosis end broken bones - torn vessels unable deliver nutrients
inflammatory response develops
Pathophysiology continued (part 2):
What does the haematoma serve as the basis for at fracture sites?
fibrin network - granulation tissue grows
new capillaries extend into tissue
phagocytotic cells, fibroblasts migrate to it
chondroblasts form cartilage
two bones become splinted by procallus/fibrocartilaginous callus (collar)
What does chondroblast do?
(form cartilage)
What do phagocytic cells do?
(removing debris)
What do fibroblasts do?
(laying down new collagen fibres)
How strong are broken bones splinted by procallus (or fibrocartilaginous callus) collar?
not strong enough to bear weight, but constitutes preliminary bridge to repair in the bone
Pathophysiology continued (part 3):
osteoblasts from periosteum and endosteum begin generate new bone - fill gap
gradually fibrocartilaginous callus replaced by bone through extensive osteogenic activity
- forms a bony callus
damaged bone repaired by new bone formation, not scar tissue
subsequent months remodelled by osteoblastic and osteoclastic activity - response mechanical stresses
excessive bone in callus removed
more compact laid down
eventually the bone assumes nowmal appearance
To summarise…
What are the five stages of bone healing?
- Haematoma
- Granulation Tissue
- Procallus(fibrocartilage)
- Bony Calluse
- Remodelling
What is the 1st stage of bone healing?
- Haematoma
What is the 2nd stage of bone healing?
- Granulation Tissue
What is the 3rd stage of bone healing?
- Procallus(fibrocartilage)
What is the 4th stage of bone healing?
- Bony Calluse
What is the 5th stage of bone healing?
- Remodelling
Approximately how long does it take for fractures to heal in Children?
1 month
Approximately how long does it take for fractures to heal in Adults?
2 or more months
Approximately how long does it take for fractures to heal in an Elderly Person?
Many months