Last reviewed: September 29, 2026

There isn’t one. Most knee replacements in use today last well, and the differences between the common ones are small.

The best evidence comes from joint registries, which track what happens to hundreds of thousands of knee replacements. In a Kaiser Permanente study of 288,584 knee replacements, implants meeting the highest international standard for 10-year durability were used in 91% of knees. Implants that fell short were used in only 3%.

How the knee works afterwards also varies little by brand. At the Hospital for Special Surgery, 4,135 patients received one of five common brands. Two years later, function scores showed no meaningful difference, and more than 80% of patients in each group were satisfied.

Newer designs are not reliably better. In the Australian registry, 11 new designs replaced older models from the same maker: 6 lasted longer, 3 lasted about the same and 2 did worse.

Custom implants made for one patient have shown no benefit over standard implants. Several studies found more repeat operations, but the difference in revision rates was not statistically significant.

Many design choices make little difference. According to the American Academy of Orthopaedic Surgeons, results are similar whether or not the back ligament of the knee is kept, whether or not the kneecap is resurfaced, and whether the implant is fixed with bone cement or without it. In the Australian registry of 478,081 knees, designs with a plastic insert that moves were redone more often than fixed ones: 4.1% compared with 2.7% within 15 years.

Age matters more than brand. In the same registry, 7.8% of people under 55 needed a major redo operation within 15 years, compared with 1.0% of those 75 or older.

The surgeon and hospital may matter too. In US registry data on Medicare patients, surgery by a surgeon and hospital doing few knee replacements was linked to more redo operations. How many they did made no difference to how much function improved.

All of these studies are observational. They show a link, not proof that the implant itself is the cause.

In general:

  • Ask your surgeon which implant they plan to use and how long they have used it.
  • Ask whether it has a track record in a joint registry.
  • Ask how many knee replacements your surgeon and hospital do each year.
  • If a newer or custom implant is offered, ask what evidence shows it lasts longer.

Drafted with AI assistance from published sources, reviewed and edited by Babak Sheikh, MD.

Sources:

This is general information about what published research shows. It is not medical advice and it is not about your situation. Reading it does not create a doctor-patient relationship with me. I am a retired orthopedic surgeon and I do not see patients. Talk with your own doctor before changing anything about your care. If something feels suddenly or seriously wrong, get medical care promptly rather than waiting.

This page is provided as is. I make no guarantee that it is accurate, complete or current, and medical evidence changes. Use of it is at your own risk.

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