Hello Gabette, Welcome to Mayo Connect, where patients and caregivers come to share experiences.

I have seen the Bleeding Edge, and it was scary. In fact, I the metal-on-metal hip implants and all the side effects. They were removed 12 years ago, and I am fine now.

One of the things we must remember is that no surgical intervention is completely risk free, and we make the choice to improve our quality of life. Even after the issues I had, I would do it again - my quality of life these past 17 years is far superior to what I would have had without surgery.

While there are a few examples of problems with the chromium cobalt knee prosthetics, they are far more rare than with the hips (which are now off the market.) As rare as they are, I suspect extensive research would show that the risks of all types of knee implants would be roughly similar.

I looked for about a half hour, and it does not seem that the incidence of heavy metal deposits and the attendant problems is as prevalent in knees as it was in hips. Probably because the mechanics are very different.

In the metal-on-metal hips, the acetabular cup and the femur implant fitted together directly, with no cushioning lining or wear layer between the two. Friction between the two metal surfaces caused a great deal of metal to be shed into the surrounding tissue.

In chromium-cobalt knee prosthetics, the femur implant and tibia implant are made of metal. Between the two is a cushion, that emulates our cartilage. It is made of a cros-linked polymer, and being softer than the metals, it is the part that compresses and wears. Hence in a fully successful implant, there is very little or no wear on the metal. It seems if problems with metal occur, it is because one or more components fail - they may remain loose within the bone, or glue may break down and cause loosening. This can happen with any knee implant, whether chromium & cobalt, titanium, or another metal.

So, if I were you, I would breathe a sigh of relief, and remain vigilant for any sign that the implant is not fully secure in the bone after it heals. Full healing and in growth takes several months, and can be confirmed with x-rays after 6 months or a year as recommended by your doctor. Then I would spend the next several months working to get that new knee in shape so I could get back to my life.

Sorry this is so long. Congratulations on your new knee. You will find many people here to coach you through recovery. Just remember the first few weeks are the worst. Ice, elevation and pain control are your best friends. And PT will hurt, but is critical to full recovery.
Sue