Fracture Repair Flashcards
What is the most common lesion in bone?
Fracture
What term describes a broken bone caused by diseased or weakened bone?
Pathologic fracture
Are all fractures pathologies?
Yes
Are all fractures pathologic fractures?
No
What phase of fracture repair occurs from onset to approximately 10 days?
inflammatory
What phase of fracture repair occurs from approximately 1 week to a few months?
reparative phase
What steps occur in the Inflammation Phase of Fracture?
- Hematoma due to rupture of BVs
- Pain caused by tearing of periosteum
- Widespread necrosis of area of fracture
- Macrophages and osteoclasts clean up debris and necrosis
- Fibroblasts migrate in and differentiate into chondrocytes (form & lay down cartilage between bone ends)
- Procallus formation begins
In what phase of fracture does the procallus begin to form?
Inflammation Phase
What steps occur in the Reparative Phase of Fracture?
- Macrophages and osteoclasts continue to clean up debris
- Neovascularization/angiogenesis of area of fracture
- Woven bone (callus) begins to ossify the procallus where blood supply is present (significant osteoblastic activity)
What radiographic sign is present in fractures during the Reparative Stage?
Hazy cloud appearance (Fx appears wider on x-ray)
What steps occur in the Remodeling Phase of Fracture?
- Callus is formed through ossification of procallus
- Callus is larger in the area of fracture, but remodels (adjusts strength & shape) due to Wolff’s Law
- Woven bone is replaced by mature lamellar bone
What cells are predominantly seen in the Inflammation Stage of Fracture?
PMN’s and macrophages; osteoclasts removing
What cells are predominantly seen in the Reparative Stage of Fracture?
Chondrocytes and osteoblasts; PMNs and macrophages
What cells are predominantly seen in the Remodeling Stage of Fracture?
Osteoblasts, osteoclasts, and osteocytes
