Clinical Outcomes & Statistics

According to the American Academy of Orthopedic Surgeons, 90 percent of patients Knee Replacement Statisticsundergoing a knee replacement experience a dramatic reduction in pain, and a significant improvement in the ability to perform daily activities. Most of these individuals are able to perform daily activities and stay active. In many cases, they’re able to resume activities, such as golf and walking, that they gave up years ago due to arthritic pain. 

A total knee replacement (TKR), also referred to as a total knee arthroplasty (TKA), relies on a mechanical implant to replace your actual knee.

Success Rates

The device usually lasts well over a decade (about 85 percent of artificial knees still work after 20 years) and the procedure is increasingly used for younger patients with osteoarthritis and other degenerative knee conditions. 

Most patients who undergo a knee replacement are between the ages of 50 and 80. The average age is about 70. Today, about 60 percent of the recipients are women. The procedure has a high success rate and is considered extremely safe and effective. Numerous studies have found that 90 percent of TKRs work after 10 years—their endurance is one reason that this procedure is so popular. 

Safety and Complications

In addition, the safety of the procedure is well documented. The 30-day mortality rate for total knee replacement is about one in 400, or .04 percent.  According to the American Academy of Orthopedic Surgeons, “Serious complications, such as knee joint infection, occur in fewer than 2 percent of patients.” As with all orthopedic procedures, blood clots represent a significant risk, but even these are not too serious a threat. Common preventative measures, such as the use of a blood thinner, minimize the risk of a pulmonary embolism—the worst potential complication of a blood clot.

One study found that only 1.2 percent of TKR patients required hospitalization within 90 days of surgery. Patients at highest risk are males over the age of 70. Cases of osteolysis—plastic or metal fragments that are released from the knee implant into the body and cause inflammation—are also uncommon. 

Unfortunately, your implant won’t last forever. Over time, the metal and plastic components wear out. Individuals who are overweight or engage in high impact activities are more likely to experience problems with the mechanical knee implant. 

In rare cases, knee implants can malfunction or come loose. This is most likely to occur at the start of rehabilitation, typically a few days after surgery. Equally rare is a device malfunction. It is usually caused by a traumatic injury. Often, when an implant fails or osteolysis occurs, a patient will experience pain and require a revision surgery. About 10 percent of patients require a revision within 10 years. This involves the replacement of worn components with new prosthetics.

Positive Outcomes

A successful TKR or partial knee replacement (PKR) typically leads to a higher quality of life, diminished pain, and improvements in mobility. One study that examined 181 knees found that both self-administered and doctor-administered pain scores decreased significantly after surgery. Patients also demonstrated significant improvements in the range of motion, specifically the maximum flexion and extension angles, of their knees.

Another 2011 study conducted at the University of Bremen in Germany found that those who undergo a TKR for osteoarthritis experience substantial improvements in the level of physical activity within a year of surgery. The study’s authors noted that a TKR “offers profound improvements of physical activity for the majority of patients.”

If you’re considering a knee replacement spend some time reading through this guide, check manufacturer’s websites and listen to the testimonials of others who have received knee replacements. It could ensure a smooth experience with knee replacement and ultimately a positive impact on your life.