Complaints over Zimmer NexGen CR-Flex Porous Femoral Component Draw Scrutiny

Aug 2, 2010 | Parker Waichman Alonso LLP

A recent study has raised questions about early failures of  Zimmer’s NexGen CR-Flex Porous Femoral component.  The study, co-authored by Dr. Richard Berger and Dr. Craig Della Valle, both surgeons at Rush University Medical Center in Chicago, found that nearly 9 percent of 108 patients examined two years after knee replacement where a NexGen CR-Flex Porous Femoral component was used required revision surgery due to loosening and pain.

The same study, which was presented in March at an American Academy of Orthopaedic Surgeons conference, also indicated that 36 percent of the those same patients examined after two years showed signs of the replacement knee loosening. Drs. Berger and Della Valle concluded that the NexGen CR-Flex Porous Femoral component “should not be used for any patient.”

Introduced in 2003, the NexGen CR-Flex Porous Femoral component is a synthetic device used to cap the thigh bone (femur) where it connects with the tibia at the knee. The component is made of a porous fiber metal and a cobalt-chromium-molybdenum alloy and is not attached using cement.

Zimmer issued a statement, essentially claiming that Drs. Berger and Valle simply implanted their devices incorrectly, and noting that the Australian National Joint Replacement Registry reveals a high success rate.  Not long after contacting Zimmer with his concerns about the NexGen CR-Flex Porous Femoral component device, Zimmer chose not to continue a consulting relationship with Dr. Berger.

Now, a prominent lawmaker is looking into the controversy.  On July 29, 2010, Sen. Charles E. Grassley (R-Iowa) issued the following letter to Zimmer Holdings, Inc. regarding the reporting of knee surgery complications when the NexGen CR-Flex Porous Femoral components were used.   The letter read in part:

“I was troubled by last month’s New York Times account of Zimmer’s response to the allegations of safety concerns raised by two of its consultants. Specifically, The New York Times reported that one of the surgeons with whom Zimmer had a financial relationship, Dr. Richard Berger, raised concerns to the company a few years ago about the premature failure of a Zimmer knee, the NexGen CR-Flex. (Barry Meier, “Surgeon vs. Knee Maker: Who’s Rejecting Whom?” The New York Times, June 18, 2010.) According to the article, Dr. Berger was a long-time consultant for Zimmer—a financial relationship that spanned more a decade—with Dr. Berger receiving more than $8 million during that time frame.”

Among other things, Senator Grassley asked Zimmer to supply a list of the safety concerns raised in the last two years by its outside consultants, and details on how it responded to such concerns.