The Zimmer Persona knee replacement system is a popular prosthetic choice for patients needing to undergo revision surgery, but it has recently become associated with major device complications.

It has been alleged that a design defect in the Zimmer knee replacement system causes premature failure, which has led many patients to ask how long these devices actually last.

Knee replacement systems typically last between 15 to 20 years, with patients having to undergo routine revision surgery for device maintenance or replacement.

However, Zimmer knee replacement systems have reportedly been failing at a much faster rate and patients are wondering why. Here are some frequently asked questions patients considering knee replacement surgery.

What is the Zimmer Persona knee replacement system?

The Zimmer Persona knee replacement system utilizes modular components between tibial plates and articular surfaces. This prosthetic system consists of the Zimmer Persona Trabecular Metal (TM) tibial plate a metal component of the device that attaches to the bone without cement.

The tibial plate attaches to the tibia by two pegs that are inserted into the bone, which are supposed to “grow” into the bone. The pegs are supposed to stabilize the implant.

Why do knee replacements fail?

There are various reasons that cause a knee replacement system to fail, according to verywellhealth.com, including wear and tear from general use. Knee replacement systems are composed of metal and plastic components that last a while but not a lifetime.

Patients typically have to undergo revision surgery to replace the old knee replacement system every 20 years or so depending on the implant. According to a recent study, approximately 94 percent of long term outcome patient who underwent knee replacement surgery still had the same implant over 20 years later.

However, it is important to note that revision surgery is often less successful than the initial implant and may require more frequent procedures.

What other factors affect knee replacement system longevity?

Generally speaking, patients who are in their 50s or younger are generally expected to have longer lasting success with their knee replacement system. Younger patients tend to live a more active lifestyle, and need to have a longer lasting prosthetic.

Other factors include how many strenuous activities patients partake in, along with the body weight of the patient. Generally, the heavier the patient and the more strenuous activity, the shorter the lifespan for the implant.

How long do Zimmer Persona knee replacement systems last in comparison?

Compared to other knee replacement systems that last between 15 to 20 years, but patients have reportedly had to undergo revision surgery due to the Zimmer Persona tibial plate after only two years of receiving the implant.

Due to the complications of the tibial plate in the Zimmer knee replacement systems, the company issued a voluntary recall in March 2015. Zimmer recalled the Zimmer Persona Trabecular Metal Tibial Plate knee component, after receiving injury reports that it had loosened from its initial position.

According to X-ray images, gaps between the prosthetic and the bone indicated “poor seating” and are a sign of early device failure. Approximately 12,000 trabecular metal components were recalled by Zimmer in a “Class 2 Recall.”