How long does a knee or hip replacement last? And am I too young?

“How long will it last?” comes up in almost every consultation. Patients want to know whether a new knee or hip is a one-time decision, and younger patients want to know whether they should wait. Here's what the best data shows.

Most knee replacements last decades

A large analysis in The Lancet pooled registry data from around the world. About 93% of total knee replacements were still in place at 15 years, about 90% at 20 years and about 82% at 25 years.¹ The American Academy of Orthopaedic Surgeons notes that more than 90% of modern total knees are still functioning well 15 years after surgery.²

In my own practice I tell patients that modern hip and knee replacements usually last 15 to 20 years, and often longer, depending on how they're used.

What about partial knee replacement?

In that same registry analysis, partial knee replacements were revised more often than total knees over the long term, with about 70% still in place at 25 years.¹ Those numbers include older implants and every technique. Precision matters a great deal with a partial knee, which is one reason I use the Mako robotic arm. In a study of Mako partial knees, 91.7% were still in place at 10 years.³ A partial knee also keeps your own ligaments and healthy bone, so for the right patient the trade-off is often worth it. I explain more in Partial or total knee replacement?

Why age matters

A replacement that lasts 20 years is a lifetime joint for a 75-year-old. For a 52-year-old, it may mean a second operation one day. A study in The Lancet estimated the lifetime chance of needing a revision. For men in their early 50s it was roughly one in three, compared with about one in twenty for patients over 70.⁴ Younger patients are more active and simply have more years for wear to build up.

That doesn't mean younger patients should suffer for a decade. It means we make the decision together, with eyes open:

• Symptoms come first. If arthritis is limiting your work, sleep or family life and conservative treatment has stopped helping, waiting has a real cost too.
• Choose the least surgery that solves the problem. When arthritis is limited to one part of the knee, a robotic partial knee is a smaller operation and keeps more of your own knee.
• Protect the joint. Staying at a healthy weight and choosing lower-impact activities help an implant last.
• Revision is not the end of the road. If a replacement wears out years from now, it can usually be revised.

The bottom line

For most people, a knee or hip replacement is a long-term solution. If you're younger and wondering whether it's “too early,” let's talk it through with your X-rays in front of us.