If you have arthritis and are facing hip or knee replacement surgery, you may be wondering how long the implant will last and if you'll need to replace the joint again some day. In this Health Alert, Johns Hopkins specialists answer this important question.
About 90-95% of hip implants last at least 10 years, and approximately 80-85% of knees last at least 20 years. Lab testing suggests that new implants could now last 20 to 25 years or longer. That's because older joint replacements made of plastic and polyethylene have now been replaced with those made of longer-lasting materials such as cross-linked polyethylene, a durable plastic; ceramic surfaces; or metal-to-metal ones that resemble ball bearings.
In the real world, how long a hip or knee implant lasts depends on how much use it gets. Although implants allow a return to active sports such as golf, biking, and swimming, they're not designed for impact sports like jogging or tennis. The trade-off may be that the hip or knee wears out sooner.
If you do need a second hip or knee implant, you will have what's called revision surgery. Sometimes people need a new hip or knee implant if the original plastic liner on the implant wears out, if the replacement loosens or breaks, or if they develop an infection.
Not all revisions require a replacement of every implant part. A simple revision is the replacement of a worn liner with a new one. A complex revision might involve grafting more bone onto the joint or dealing with an infection. In the case of infection, the replacement joint would have to be removed, and you would need intravenous antibiotics for six to eight weeks before the replacement could be reinserted.