Deciding on Surgery
Most knee replacements last many years, and the large majority are still working two decades after surgery. But no surgeon can tell you exactly how long yours will last, and the answer depends a lot on your age, your weight and how you use your knee. This guide covers what the research shows, whether one knee replacement can last for life, what to weigh if you are younger, which signs point to a problem and when a revision is considered.
Key takeaways
A knee replacement is built to last for many years, and most people never need another operation on the same knee. Think of the research as odds, not a guarantee. Your own result depends on you, your knee and how the surgery is planned and performed.
The most cited long-term figures come from a 2019 review in The Lancet. It looked at how many total knee replacements had not needed revision surgery, meaning a second operation to repair or replace the implant:
| Years after surgery | Knees that had not needed revision |
|---|---|
| 15 years | about 93% |
| 20 years | about 90% |
| 25 years | about 82% |
The American Academy of Orthopaedic Surgeons (AAOS) likewise reports that more than 90% of modern knee replacements are still working well at 15 years. Read these numbers with care:
For many people, yes, and age at surgery matters most. If you have your surgery in your late 60s or 70s, the long-term figures suggest your original implant is likely to be the only one you will need. If you have it in your 40s or 50s, the implant has three or four decades to cover, so a revision later is a real possibility.
A higher chance of needing a revision later is not a certainty, and many younger patients never need a second operation.
There is no age at which knee replacement becomes right or wrong. It is a trade-off, and these are the questions that help you weigh it:
A younger patient with severe arthritis may reasonably decide not to wait, while another does well with other treatments for years. Dr. Kalender decides this with you after reviewing your symptoms, imaging and health, and he tells you honestly if waiting makes sense. A question worth asking any surgeon: “Given my age, how would you plan for the possibility of a revision?”
Most aches after knee replacement are not a failing implant, but these signs are worth an evaluation.
A revision means replacing or repairing part or all of the implant. Surgeons consider it for:
Your surgeon first works out what is going on. That usually means an examination, X-rays (sometimes a bone scan, MRI or CT), blood tests and, if infection is possible, a sample of fluid from the joint. Many problems are treated without revision first.
A revision is generally a longer, more complex operation than the first replacement. It may need specialized implants or bone grafting, it carries a higher risk of complications such as infection, and recovery is usually slower. That is one more reason why a carefully planned first surgery matters.
A knee replacement is a long-term decision, so the plan matters as much as the operation. This is what to expect from Dr. Kalender:
What he does give you is a plan built around you.
Low-impact activities such as walking, swimming, golf and cycling are generally considered realistic. High-impact activities can speed up wear. Ask your surgeon what is right for you.
Periodic check-ups and X-rays are recommended, so problems can be caught early. Your surgeon will tell you how often.
Free online consultation
Dr. Kalender reviews your imaging, talks it through with you and tells you whether surgery makes sense now. Free, with no obligation.
Pain-free knee replacement in Istanbul for patients traveling from the USA. Orthopedic & trauma surgeon at Dora Hospital.
Dora Hospital · Fulya Mah. Yavuz Sk. No:7, 34394 Şişli / Istanbul, Türkiye
The information on this website is for general guidance and does not replace a medical consultation. © Dr. Mahmut Kalender