It depends on what bone has a hairline fracture
A hairline fracture of a bone in the hand or foot will likely heal in 6 weeks, but a hairline fracture (a break in the bone without any displacement of the fracture) of the femur, the scaphoid, and the tibia (among others) could take longer, on the order of 10-12 weeks. Make sure you see an orthopaedic surgeon to have it treated appropriately!
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