An advisory panel for the FDA has decided that the risks involved in using metal-on-metal hip implants in hip replacement surgery outweigh the benefits, yet shied away from actually banning the devices, according to reports by the Associated Press and other media outlets. The panel announced its conclusion on Thursday at the end of a 2-day inquiry into the implants' effectiveness and dangers.
The FDA had announced the inquiry back in March of this year, amid growing concerns that the metal-on-metal hip implants were not lasting as long as their ceramic or plastic counterparts. There was also preliminary data to suggest that the metal-on-metal hip implants were more likely to require subsequent medical interventions after the initial hip replacement surgery.
Researchers at the University of Bristol in the U.K. had been among the first to raise the alarm, earlier that same month. Studies had shown that not only did the devices have a higher failure rate than initially thought, but that there was a risk that particles of cobalt or chromium may seep into the blood, bone, and surrounding tissue, which in some cases can cause further disability, according to a Bloomberg News report at the time.
Defenders of the metal-on-metal hip implants cited contributing factors to explain the higher failure rate of the devices. Earlier this year at the American Academy of Orthopaedic Surgeons' annual conference, researchers said a patient with a metal-on-metal hip implant who continued to smoke after hip replacement surgery more often had complications than those who did not, according to Drugwatch. This appeared to attempt to place some of the impetus for the device's failure rate on the patients themselves, although it was later revealed that the manufacturers had failed to warn doctors or patients of that risk.
Researchers also noted that women, particularly those who had undergone hip replacement surgery with a metal-on-metal implant from the year 2004 and onward, were far more likely to have problems with the device. The implication being that the implants may be more suitable for use in one gender over another.
The FDA too had continued to defend the implants right up until Thursday, asserting that the failure rate and number of complications reported with the device appear to be the same for both ceramic and plastic implants as well, according to HealthDay. The agency had previously ordered additional "post-market" studies of the device, but most are still incomplete.
Thursday's decision will end up slowing the use of the devices in hip replacement surgeries going forward. Yet, despite the evidence against the devices, the FDA stopped short of issuing even a temporary ban against their use in the U.S. like it probably should have, given the now-proven risk of metal absorption and the higher failure rate, particularly among women who have been implanted with the device.
Vanessa Evans is a freelance writer based in Michigan, who frequently covers health and nutrition news.
- hip replacement surgery