There isn’t a lot of conclusive evidence from studies to answer this question. An orthopedic surgeon from the Mayo clinic did so a review of what’s been reported so far when it comes to plates, screws, pins, and other fixation devices of this type left in the body.
He found there have been concerns raised about titanium found in the blood, suppressing the immune system, and/or causing cancer. There is evidence that the metal can cause the entire immune system to be suppressed (under functioning). This immune system shut down could result in infections.
Some studies have shown that metal implants can cause an increase in white blood cells called lymphocyte reactivity. There is a worry that this effect could cause implant loosening or failure, though it hasn’t been proven yet.
Another potential problem with titanium plates is the debris that occurs. Tiny flakes of this metal chip off and enter the bloodstream, nearby soft tissues, and/or joint. Both titanium and stainless steel have been found in all these anatomical areas of the human body (titanium slightly more often and in greater amounts than stainless steel). Metal debris is more likely to develop when the implant is rubbing against another surface. This wearing or rubbing phenomenon is called fretting.
Then the question arises: can this metal debris lead to the formation of cancer? Studies in mice show there is the potential for metal wear debris to damage chromosomes making it a potential carcinogen (cancer producing). Next, developers of these products asked if coating the plate would protect the body from corrosion or metal debris? This question remains unanswered so far.
Surgeons share patients’ concerns about leaving metal plates in the body but do not want to perform an additional surgery to remove them if it’s unnecessary. And sometimes when plates are used to hold bone together after a fracture, bone grows around them embedding this fixation device too much to remove it easily.
Without adequate scientific evidence to answer your question directly, it may be best to go with whatever recommendation your surgeon makes. He or she may have specific and compelling reasons to suggest leaving the hardware in place (or removing it). Clearly, more research is needed to look into this potential problem.