An editorial in the British Medical Journal (BMJ) is calling on metal-on-metal hip replacement manufacturers to cover the cost of follow-up screening for patients who received the controversial implants.
The publication of the editorial comes just months after regulators in the U.K. urged more than 50,000 metal-on-metal hip replacement recipients to undergo imaging and blood testing to ensure their implants are functioning properly – even if they are not currently experiencing pain, swelling or other signs of failure.
Metal-on-metal hip implants consist of a ball, stem and shell, all made from cobalt-chromium-molybdenum alloys. Introduced in the 1990s, the devices were marketed as a more durable option for younger, active patients. However, in recent years, studies have suggested that some all-metal implants can shed dangerous amounts of toxic metal ions into the area around the joint and even the blood stream, resulting in adverse local tissue reactions and other complications that necessitate revision surgery to remove and replace the device.
According to the BMJ, around 65,000 metal-on-metal hips have been implanted in the U.K., while 17,000 patients have experienced complications associated with the devices. Many those patients have been forced to undergo revision surgery.
In June, the U.K.’s Medicines and Healthcare Products Regulatory Agency (MHRA) recommended that patients who currently have metal-on-metal hips undergo more stringent screening for complications, including yearly use of the patient-reported Oxford hip score to assess pain and function; annual blood ion testing regardless of patient symptoms; and imaging with plain radiography, MARS MRI, or ultrasonography. The new guidelines also recommend that surgeons consider revision surgery when screening suggests something is amiss.
Writing in the BMJ, Andy Carr, Nuffield professor of orthopaedic surgery at the University of Oxford, notes that the implementation of the MHRA’s recommendations will lead to testing in tens of thousands of patients.
“The new requirement for review of more than 45,000 asymptomatic patients will also be costly,” he wrote. “There is a strong case for manufacturers bearing some, if not all, of this burden.”
In the U.S., the Food & Drug Administration (FDA) has also been acting to mitigate the danger posed by all-metal hip implants. In a January 2013 Safety Communication, all-metal hip patients were urged to seek medical attention if they experienced any issues with their implants. 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.
Thousands of hip replacement lawsuits have been filed in U.S. courts on behalf of individuals who allegedly experienced premature device failure and other debilitating complications due to metal-on-metal implants. 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.
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.
Thousands of DePuy hip replacement lawsuits involving a metal-on-metal version of the company’s Pinnacle hip system remain to be litigated.