The idea that the metal we’re installing in people’s knees may be causing allergies has been talked about at many orthopedic conferences over the last few years. There is a growing realization that knee replacement can cause tissue reactions due to wear particles shed from these devices. Now a research study reported in the November 3, 2015 issue of the European medical journal Knee Surgery, Sports Traumatology, Arthroscopy links any random patient allergy prior to surgery to a poorer knee-replacement outcome.
A knee replacement is the amputation of a joint and insertion of prosthesis made of metal, ceramic, plastic, or some combination of these materials. That these devices are shedding wear particles has received a lot of attention. In some patients, metal ions from the knee-replacement device have been shown to build up in the blood. In patients who have a known jewelry allergy, the risk of being allergic to the metals used in these knee-replacement devices is high. Some of the plastics being used in knee-replacement prostheses also cause allergies in patients. In patients who are allergic, the devices are more likely to fail, cause chronic pain, or need to be replaced sooner. Until now, it was assumed that allergy-related issues were confined to patients with a specific allergy to the substance used to make the knee-replacement device. The European study suggests that the allergic reaction issues may encompass all patients who have an allergy to anything.
The European study involved hundreds of patients in Spain who underwent a knee-replacement surgery for osteoarthritis. Roughly two-thirds of the patients reported no allergy on their medical charts, while about one-third had reported at least one allergy. The group with at least one reported allergy fared worse in outcome scores than the group without any allergies.
About one-third of the population tend to have allergies, which means that their immune systems may be more “jacked up” than those of most people. Allergic people may be much more sensitive to having a foreign body shedding particles as it wears, and this causes their immune systems to attack the device. When your body rejects something, you can bet that swelling and pain will ensue. It’s also likely that there will be poorer bonding of bone to the device in a body that is attempting to reject the device.
If you have a known allergy to something, you may want to think twice about getting a knee replacement. While more research needs to be done, the European study adds to the growing evidence that what we implant in patients may not be compatible with their bodies.
“Avoid Knee Replacement If You Have Allergies” first appeared as a post on the Regenexx blog.
Like all medical procedures, Regenexx procedures have a success and failure rate.
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