Hip and Knee Care LibraryThe AAHKS patient education library contains articles on caring for your hips and knees before and after joint replacement surgery written by surgeon members of the American Association of Hip and Knee Surgeons.
Recovering from Hip or Knee Replacement Surgery
If you are anticipating a hip replacement or knee replacement, here are frequently asked questions about recovery following surgery answered by Stephen J. Kelly, MD.
What is the chance of my body “rejecting” the implant?
Unlike an organ transplant, the risk of your body rejecting the artificial hip or knee parts is exceedingly rare. The materials used in the typical replacement surgery are well tolerated by the body and have a long track record of successful implantation. While in rare cases the parts may become loose or infected, this is typically related to other factors and not due to your body “rejecting” the parts.
How do I know if I have a recalled implant?
Most modern hip and knee replacement parts have a long history of excellent safety and few known mechanical issues. In recent years, there have been a handful of very specific implants involved in a recall process due to metal reactions, higher than expected failure rates and other unanticipated problems.
Most companies offer numerous models and designs of their implants (like the car makers and the different makes and models they offer). It is important to keep in mind that just because one model has been recalled, the company is likely to have many others that are performing very well.
The vast majority of patients will not experience an issue with a recalled implant. If you are concerned about your particular type of replacement, we recommend you contact your surgeon’s office to ensure that your implant has not been involved in a recall.
I have a history of nickel allergy and/or break out in a rash with certain types of jewelry. How do I know if I am allergic to the implants?
The metals used in hip and knee replacements are generally well tolerated by the body, even in patients who have skin sensitivity to certain metals (this type of allergy involves a different part of your immune system).
For more detailed information, please see the FAQ on metal allergy and joint replacement.
How do I know if I have developed metal poisoning from the replacement parts?
While recent concerns have been raised about the potential for developing metal poisoning (cobalt or chromium toxicity) from hip and knee replacement parts, such cases are thought to be exceedingly rare. In some cases (typically associated with very specific models of hip replacement – most of which are no longer used by surgeons), excessive levels of metal ions may be generated by the implant surface contact points. These metal ions may in turn cause a reaction in the tissue around the joint and can, in isolated cases, lead to tissue and/or bone destruction.
If your implant is functioning well and you have little pain or change in comfort level, chances are you are at very low risk of a metal reaction.
If you are experiencing new or worsening pain, contact your surgeon to be evaluated. Again, cases of metal poisoning from orthopedic implants are very rare and generally occur in the tissues around the joint involved. While in theory hip and knee implants can lead to elevated levels of metal ions in the blood, systemic side effects of metal poisoning from joint replacements (kidney damage, neurologic symptoms, psychosis) are exceedingly rare.
Can I have a hip or knee replacement if I am allergic to metal?
Yes, you can still have a joint replacement if you are allergic or sensitive to metal. Metal reactions are very rare. If there is a concern about metal allergy this is an individual discussion to have with your surgeon
This article has been written and peer reviewed by the AAHKS Patient and Public Relations Committee and the AAHKS Evidence Based Medicine Committee. Links to these pages or content used from the articles must be given proper citation to the American Association of Hip and Knee Surgeons.