The question of the safety of leaving metal plates, screws, wires, and pins inside people’s bodies after surgery to fix fractures and other types of bone damage remains a largely unanswered one. Even with the research that’s been done, we don’t have any idea how much metal debris in the bloodstream or embedded in the nearby soft tissues is acceptable and/or safe (or unsafe).
A lot of studies in this area have been done on mice and rabbits. The results aren’t conclusive enough to provide guidelines for humans. Clearly, there are certain situations in which some patients are at greater risk from these implants. For example, the larger the surface area exposed to the implant, the greater the exposure and increased risk of metal debris entering the bloodstream.
Intramedullary pins or nails such as you have do show the highest risk of metal released into the body. Some metals are more biocompatible (e.g., titanium is better than stainless steel). But even these metals are not without some reactions and responses within the body.
Accumulations of debris are more likely when the implant is rubbing against another surface. This wearing or rubbing phenomenon is called fretting. A stable implant in good position and alignment will have minimal fretting.
Your surgeon may want to monitor your situation in order to see if the amount of metals detected in the blood are staying steady or increasing. Even with removal of the fixation device, it can be months up to a year or longer before changes are seen in your blood levels.