Zimmer Hip Replacement Complications - FDA's Lax Approvals

Zimmer Hip Replacement Complications Linked to FDA Shortcomings

Dawn Snyder | October 16th, 2014

zimmer metal hip implantIn the minds of countless Americans, the U.S. Food and Drug Administration (“FDA”) provides consumers with a certain level of protection from unsafe or ineffective drugs and medical devices. But according to a recent study, relaxed supervision by the FDA has led to major shortcomings in testing and reviewing new medical devices.

There is reason to believe that tighter regulations could prevent dangerous results like the revision surgeries that some patients undergo to correct Zimmer hip replacement complications and other medical device problems.

“Substantially equivalent” devices not subjected to testing

In the study, published in JAMA Internal Medicine, out of the study’s sample of 50 new implants pending application to the FDA, the manufacturers of 42 of the devices did not submit any scientific evidence supporting its safety.

A key problem is that most of the new devices are submitted for FDA review under provision 510(k) as “substantially equivalent” to a device that it has already approved. Under the regulations for “substantially equivalent” devices, manufacturers do not have to perform and submit new clinical testing – just prove that the device is similar to a device that was already found by the FDA to be safe and effective.

Even with the more relaxed requirements under the “substantially equivalent” application process, the FDA is not policing the submissions. For instance, according to Diana Zuckerman, the president of the National Center for Health Research, manufacturers must submit a sufficiently detailed summary of the scientific evidence that provided for FDA approval of the predecessor device; instead, the companies often simply state that no testing was performed and fail to mention any scientific evidence in support of safety.

Pre-market testing may have prevented Zimmer hip replacement complications

The Zimmer hip problems that many patients have experienced is an illustration of the injuries that can result from FDA’s disinterested review of “substantially equivalent” medical devices.

The Zimmer Metasul Durom hip system was just one such device. This metal-on-metal hip was introduced in 2003 but rather than undertaking current safety testing and trials, the manufacturer, Zimmer, Inc., applied for FDA approval under the 510(k) process. The hip system was fast-tracked to market in 90 days because the manufacturer represented to the FDA that it was “substantially similar” to a prior Zimmer device. What should be noted, however, is that the earlier version of the Zimmer metal hip was abandoned for safety reasons in the early 1970s.

Even though the Zimmer Durom hip system did not undergo trials, approximately 12,000 people were implanted with it between 2006 and 2008. But reports in 2008 estimated that 20-30% of the recipients would require revision surgery to correct complications caused by the replacement device. Zimmer pulled the hip from the market based on the high failure rate.

Since Zimmer pulled the Durom system from the market, hundreds of Durom Cup recipients have filed lawsuits over Zimmer hip replacement complications. Another Zimmer hip system, its Trilogy Acetabular System, was also granted 510(k) approval by the FDA and has also become the target of personal injury lawsuits.


  1. CBS News, Not enough safety testing on medical implant devices, studies claim, http://www.cbsnews.com/news/not-enough-safety-testing-on-medical-implant-devices-studies-claim/

  2. JAMA Internal Medicine, Assessing the Safety and Effectiveness of Devices After US Food and Drug Administration Approval, http://archinte.jamanetwork.com/article.aspx?articleid=1910557

  3. ScienceWorldReport, FDA Does Not Properly Regulate Medical Devices, Report Reveals, http://www.scienceworldreport.com/articles/17699/20141006/fda-does-not-properly-regulate-medical-devices-report-reveals.htm

  4. National Institute of Health U.S. National Library of Medicine, Failure of the Durom Metasul® Acetabular Component, http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2806993/