Bone Repair

Fracture a break in a bone 4 classification position of the ends after fracture nondisplaced: normal alignment displaced: bone ends out of alignment completeness of break complete: bone broken through incomplete: bone partially broken orientation of break relative to long axis linear: breaks parallel to long axis transverse: breaks perpendicular to long axis penetration of skin opened (compound): bone breaks through skin closed (simple): bone does not break through skin

Bone Repair hematoma - blood clot new blood vessels begin to invade osteoblasts begin building spongy bone osteoclasts start cleaning up cartilaginous callus - fibrocartilage fills in gap between bone parts bony callus replaces fibrocartilage (endochondral) bone remodelling osteoclasts remove excess bone

Treatment reduction - realignment of broken bone ends closed (external) - doctor physically realigns the bone ends open - bone ends are secured together surgically with pins or wires casts to immobilize fractured bones Philadelphia 1876 healing time depends on type of break typically 6-8 weeks