How many years does a knee replacement last?

How many years does a knee replacement last?


My name is Dr. Salam, and I am a consultant orthopedic surgeon in One Care Medical Center, a premier 100 bedded orthopedic hospital in Coimbatore. In today’s post, we are going to discuss exactly ‘how many years does a knee replacement last?’

Lets first answer a few questions about knee replacement though.


When do you actually need a knee replacement?

You only ever need a knee replacement, if your knee joint gives you chronic pain, stiffness, instability or an utter loss of your day to day function. In a healthy knee joint, protective cartilage covers the ends of the bones that actually form the joint, allowing it to smoothly move against one and another.

In patients who develop arthritis though, damage occurs to these cartilaginous structures. So what basically happens is that the cartilage wears out. The bone starts rubbing out on each end leading to severe pain and joint wear & tear.

In a typical knee replacement procedure, the worn ends of the bones are replaced with metal/plastic components that fit the bone. These components allow the joint to move freely. Because, these parts interlock as well, the joint will be stable.

How long does a knee replacement last?

An artificial knee can never give the same longevity of your true biological knee joint. Since most replacement parts are made of plastic or metal, they are also subject to routine wear and tear.

Many studies have shown that good quality implants can last the better part of 20 years in most patients. While this result cannot generalized to all patients undergoing knee replacement, a small proportion of patients will require a second replacement after the first one. The actual number is usually less than 5%.

Several factors apart from intrinsic implant-related factors can affect the outcome of a knee surgery. These include

1. The age of the patient:- The younger patients require the implant to last longer in general. Thus, the younger patient may require a revision replacement later in life.

2. Activities:- Some activities are OKAY with knee replacement, but some activities are not. High impact sports may not be safe post a knee replacement

3. Body weight:- Overweight individuals are at an increased risk at making knee joint last less long.

4. Osteoporosis:- Osteoporosis of the bones around the joint should be adequately managed before contemplating on a knee replacement.

Choosing newer implants
Choosing newer implants may sound exciting with a lot of manufacturers claiming tall results on their product. However, long-term safety data is seldom available with newer implants in the industry. Thus, it would be wise to discuss with your orthopedic surgeon on the safety of proceeding with newer implants/technology.