I had a titanium intermedullary rod emplaced in my right Tibia following an MC acident in 1997, where I got T-boned while going through an intersection. I suffered a compound/open tib-fib fracture, and prior to this I had never expected to see any of my bones up close and in person.
At the time, my surgeon gave me about a 50-50% chance of avoiding a lower leg amputation, because I had shattered about 6 inches of my tibia into little tiny pieces. The fibula fracture that came with it apparently wasn't cause for much concern in light of the more serious breakage.
The surgeon later told me that they wore out seven drill bits while trying to bore out the center of my tibia, and had to use the smallest diameter rod they had, due to my apparently outstanding bone density. Woo-hoo!
Anyway, they put the rod in. I was told it could be removed at some later time if necessary, but it would rpobably be with me forever unless there was a damn good reason to take it back out.
I figured I never had to worry much about breaking that leg again...maybe "bending" it could be a problem.... thankfully, that issue has never come up so far.
I've managed to avoid aquiring any further metal pieces, but thought I might get another last year when I broke my collarbone in another crash. lucky for me, it healed naturally.