Hi! I agree with nospam that it is likely rare. I remember asking my surgeon this very question before I had my 1st TOS surgery 9 years ago. I seem to remember that he said something along the lines about removing most of the rib so there was no chance of re-growth. So far, there is no evidence of re-growth on that rib. Hope this holds true for the other side as surgery is scheduled in a few days.