Gene May Predict Those Most Likely to Suffer Metal-on-Metal Hip Complications

Published on December 27, 2017 by Sandy Liebhard

A recently published Australian study suggests that patients with a certain gene may be more likely to experience the types of complications that have led thousands of people throughout the world to file metal-on-metal hip implant lawsuits against DePuy Orthopaedics and other medical device manufacturers.

Findings Could Lead to Test That Would Help Doctors Determine Appropriate Hip Implant

Prior to the publication of the award-winning research by scientists at Adelaide’s Lyell McEwin Hospital, there was no way to determine which patients might be most at risk for the painful pseudotumors experienced by some metal-on-metal hip replacement recipients. According to News9 in Sydney, the authors of the study are hopeful that their research will ultimately lead to a test that will help doctors choose the appropriate device for each individual patient.

“If we could pick the patient prior to the operation who would safely receive one of those implants, they might get decades of good use out of them,” said co-author Dr. Andrew Kurmis.

Metal-on-Metal Hip Complications

Metal-on-metal hip implants, which consist of a ball, stem and shell constructed from cobalt-chromium-molybdenum alloys, were introduced in the 1990s and marketed as a more durable option for younger, active patients in need of hip replacement.  However, studies published in recent years have suggested that the devices can shed dangerous amounts of toxic metal ions into the tissue around the joint and even the blood stream, resulting in adverse local tissue reactions, pseudotumors and other complications that necessitate revision surgery to remove and replace the device.

In a January 2013 Safety Communication, the U.S. Food & Drug Administration urged metal-on metal hip implant patients to seek medical attention if they experienced any issues with their devices.  Doctors in the U.S. were advised to consider metal ion blood testing and imaging for symptomatic patients.

In 2016, the FDA finalized new regulations that, among other things, banned medical device manufacturers from obtaining regulatory clearance for metal-on-metal hips via the agency’s 510(k) protocols. This program does not require that a device be subjected to human clinical trials if a company can show that the product is “substantially equivalent” to one previously approved by the agency.

Metal-on-Metal Hip Litigation

Tens of thousands of hip replacement lawsuits have been filed in U.S. courts on behalf of metal-on-metal hip recipients who allegedly experienced premature device failure and other debilitating complications due to metal shed by the devices. In November 2013, DePuy Orthopaedics agreed to pay $2.5 billion to resolve claims involving its ASR line of all-metal hips, which were recalled in August 2010.

DePuy is still facing thousands of  hip replacement lawsuits involving a metal-on-metal version of the company’s Pinnacle hip system. Four federal Pinnacle claims have gone to trial since October 2014, three of which concluded with multi-million-dollar verdicts for plaintiffs.

In February 2014, Biomet Inc. agreed to a $56 million settlement that resolved many of the hip replacement lawsuits involving its M2a line of metal-on-metal hips. And last November, Wright Medical agreed to pay $240 million to settle nearly 1,300 cases involving its all-metal Conserve, Dynasty and Lineage hip replacements.

Similar lawsuits have been filed against metal-on-metal hip manufacturers in the U.K., Australia, and Canada.