Researchers: Metal-on-Metal Hips Implants Should be Banned
Posted 13 March 2012 | By
Researchers working with the world's largest database on hip replacements have found so-called metal-on-metal hip implants are associated with high rates of failure, and recommended that they not be implanted in patients going forward.
Writing for the journal The Lancet, the researchers found that more than half a million US patients and 40,000 UK patients are implanted with the devices and subject to a higher risk of device failure than those patients with non-metal hip sockets.
"Metal-on-metal stemmed articulations give poor implant survival compared with other options and should not be implanted," wrote the researchers. "All patients with these bearings should be carefully monitored, particularly young women implanted with large diameter heads."
Failure rates were related to hip size, with larger hip implants failing at a 2% greater rate per millimeter increase in size.
The metal-on-metal devices were cleared for marketing approval in the US via the 510(k) medical device pathway, which relies on a device being "substantially equivalent" to a predicate device instead of undergoing clinical trials.
Bloomberg - Metal-on-Metal Hip Implants Should Be Banned, Review Says
The Lancet - Failure rates of stemmed metal-on-metal hip replacements: analysis of data from the National Joint Registry of England and Wales