fibular sesamoid fracture / osteonecrosis

Hello

I have a non healing foot fracture. I have been wearing a walking boot air cast since sept. I did 2 mri tests and 1 ct scan. My doc thinks osteonecrosis is possible. My questions are why can't osteonecrosis be determined? If I do have this disease what may happen? Will other bones break as well and finally how can I find the best doctor for a 2nd opinion concerning this?
Thank you.

[Yena H Do, DPM]

if you have osteonecrosis, the MRI will show darkening at the sesamoids.
if this is the case, you need to be nonweight bearing to allow the bone to heal.
if this continues to become a problem, you have to take out the sesamoid.