A new study is reportedly raising more questions about Zimmer Holdings Corp.’s NexGen Knee replacement products. According to a report from Dow Jones Newswires, the single-center study, conducted by researchers at the Mayo Clinic, found that using a Zimmer NexGen knee with a specific type of tibial component can lead to destruction of the implant in a small number of recipients.
The new study is expected to be presented Thursday at a meeting of the American Academy of Orthopaedic Surgeons. The Dow Jones Newswires report did not specify the tibial component cited in the study, but a spokesperson for the company said that the component represents 1.2% of Zimmer’s tibial sales.
According to the study’s abstract, Mayo clinic researchers looked at 1,373 total knee replacements performed at a single center between 2000 and 2011 using a Zimmer NexGen knee with the specific type of tibial component. In about 3.9% of cases, the implant failed for various reasons. In half of the failures, a problem occurred where the implant became loose from the surrounding bone. Of those cases, 80% were the result of isolated debonding, where the implant comes loose from cement.
While it’s unclear how widespread the isolated debonding problem was, the researchers noted that it wasn’t seen with other implants used at the center. A spokesperson for Zimmer told Dow Jones Newswires that high-volume users of the system “haven’t reported any similar event.”
As we’ve reported previously, Zimmer has been named in numerous lawsuits throughout the country involving various NexGen knee components, including Zimmer NexGen CR-Flex femoral components, Zimmer NexGen MIS tibial components and Zimmer NexGen LPS-Flex femoral components. All of the lawsuits allege that plaintiffs experienced problems following knee replacement surgery as a result of design defects with the Zimmer NexGen components. In many cases, those problems often resulted in the need for painful revision surgeries.
Last August, all federal NexGen Knee Replacement component lawsuits filed in federal courts were centralized in a multidistrict litigation (MDL) in U.S. District Court for the Northern District of Illinois. In December, attorneys for Zimmer filed a motion seeking the centralization of New Jersey state lawsuits involving certain NexGen Knee components in Middlesex County, which they say is the least congested venue and centrally located for all parties