The FDA announced a voluntary recall of the Zimmer Persona Trabecular Metal Tibial Plate in March 2015 by Zimmer Biomet, after numerous patients reported serious Zimmer Persona knee problems.

The Zimmer Persona knee problems indicated in injury reports have included device loosening and need for revision surgery.

The Zimmer Persona Trabecular Metal Tibial Plate knee implant is designed to replace damaged or deteriorated knee bones without the use of cement. The device works by attaching to the tibia by using two pegs which are planted directly into the bone to simulate natural bone growth.

The pegs are meant to stabilize the implant, but recent injury reports indicate there could be a serious design flaw or manufacturing error with the pegs.

Overview of Zimmer Persona Knee Problems

Patients’ injury reports indicate the Zimmer Persona knee implant may show signs of “poor seating” based on the state of the device in diagnostic images. Usually poor seating is indicated by gaps occurring between the knee implant and knee bone which can be seen on X-ray images.

Poor seating often occurs due to implant not being properly implanted, causing the device to loosen. Early signs of device loosening are shown by radiolcuent lines, which can be seen once the device begins to move out of place. When the device loosens, the trabecular metal plate comes loose from its original attachment and can ultimately lead to device failure.

Device loosening is one of the most prevalent causes for revision in total knee arthroplasty. Along with device loosening, the Zimmer Persona knee problems that result in a revision surgery include but are not limited to:

• Persistent pain
• Loosening of device
• Lack of in growth
• Component failure
• Loss of fixation
• Globally tight knee
• Instability
• Fracture
• Patella tracking issues

It is important to note that revision surgery is considered riskier than the initial implant surgery, because of the higher risk of infection.

Zimmer previously announced a voluntary recall of the Zimmer Persona Trabecular Metal Tibial Plate implant in February 2015, recalled nearly 12,000 knee implants. The FDA followed suit soon after in March 2015, giving the recall a Class 2 category.

This category of recall is reserved for drugs and medical devices that have been indicated to cause temporary or reversible injuries. According to the FDA, all lots and sizes of the particular Zimmer Persona knee implant were affected.

The Zimmer Persona knee implant was approved to go to market by the FDA in late 2012 through the agency’s 510(k) program.

Through this program, medical devices need to prove they are substantially similar to another product already on the market. If the device qualifies for this program, then it can bypass the FDA’s rigorous pre-market review.

While this program allowed the Zimmer Persona knee implant to move onto the market quickly, this may have prevented the device from receiving a sufficient safety profile. Patients who had to undergo revision surgery due to Zimmer Persona knee problems may be able to file legal action against the manufacturer.