How long will a new knee joint last?
Knee replacements do wear and can eventually wear out. Unfortunately, an artificial knee is not as durable as your own natural knee. Because the knee replacement implants are made of metal and plastic, these materials do wear over time, similar to the treads on your car tires.
Studies show that knee replacements can last more than 20 years. This is dependent on many factors. The activity level, weight and age of the patient can effect the longevity of the joint. One very large study found that 80% of knee replacements were functioning well after 15 years in the younger (less than 65) patients, and 94% of the older (over 65) patients.