5 stages of fracture healing
stage five
bone remodelling
stage three
callus formation
stage one
fracture and inflammatory phase
granulation tissue formation
fibroblasts are attracted to area of injury and there is a growht of vascular tissue; nutrient and oxygen supply during early progress is significant; stage lasts approx 2 weeks
stage two
granulation tissue formation
stage four
lamellar bone deposition
lamellar bone deposition
strengthening phase where ossification is mineralized; meshlike callus of woven bone is replaced by sheets of mineralized bone that are organized parallel to axis of bone and are mechanically stronger than bone of callus
fracture and inflammatory phase
bleeding initially occurs bw edges of fractured bone, and a hematoma develops during first few hours and days; inflammation in area causes vascular permeability and attraction of WBCS
callus formation
callus formed; consists of osteoblasts and chondroblasts; cells syntehsize extracellular organic matrix of woven bone and cartilage, producing newly formed mineralized bone within 4 to 15 weeks