Hi. You can have a blood test done for implant allergies. It's called an LTT test. It will test for all metals and cement allergies. Any skin allergy tests you might have had done previously are considered to be unreliable. I've also had doctors tell me that implant allergies are a fallacy which I thought was ridiculous since I've read multiple reports proving otherwise. The different implants have different allergy possibilities. Cobalt is still being used. You can find out who is your TKR manufacturer, the type of metals and the serial # from your surgeon or hospital if you don't have that information. Nickel, Cobalt and sometimes Chromium in some TKRs have been found to be major allergies for some people in addition to some cements. You can order a test kit from Orthopedic Analysis in Chicago. Go to their website to order the kit. The website is the same as their name. This silly site would not let me post the website link which is totally UNHELPFUL to people on this site. STUPID. Why would I post a spam site? Just adding to people's frustration which none of us need. It must be paid for up front and then submitted to your insurance for payment as they don't deal with any insurance. They leave that up to you the patient. Whether the insurer will reimburse you is always the question. Its about $550 dollars. I'm just now ordering the test myself. I will probably have more info later after I've done this myself. If a test is positive for a cement allergy, there is one cementless TKR on the market now -- Zimmer BioNet. You would need to research the metals in each TKR manufacturer to find the correct TKR to work around your allergies. Your surgeon could confirm the metals used in a particular TKR or a manufacturers rep. This same info would also apply to hip replacements. If you have any other questions, let me know.