Hi, thanks for writing to HCM.
(break in the continuity of bone) always needs immobilization in some form to allow it to heal and unite.
The hairline fracture (as per your description) is most likely to become a displaced fracture with weight bearing on it (in the form of walking). So, I suggest you to rest your leg for atleast 3 -4 weeks after which you have to take an Xray again to check the status of the fracture.
If the fracture has united and if you dont have any pain or tenderness at the fracture site, then you are allowed to bear weight on the involved leg.
Itching at the site of a fracture is considered as Normal, it will resolve on its own.
Hope this information is helpful. Good day