Although metal-on-metal hip implants have high failure rates for both sexes, women in particular have suffered from receiving the faulty devices, according to a report in the Guardian.
U.K. joint replacement experts called for the metal-on-metal implants – where both the ball and socket are coated in metal – to be banned following the medical journal Lancet’s release of a report earlier this week finding “unequivocal evidence” of high early failure rates.
The research, based on the National Joint Registry of England and Wales, found that 6.2 percent of the metal-on-metal implants failed within five years, compared with 2.3 percent of ceramic-on-ceramic implants and 1.7 percent of metal-on-plastic types.
But the size of the implant’s “head,” or the part fitted over the bone-end that fits into the socket, was a factor. So was the gender of the transplant recipient.
Larger heads failed sooner, with the equivalent to a 2 percent increase in the risk of failure for each 1mm increase in head size. In women, failure rates for metal-on-metal were up to four times higher than for other types, and were also higher compared with men even with the same head size.
At seven years after surgery, some revision rates were as high as 10 percent, such as for 55-year-old women with a 46mm head implant. For women with a 36mm head, the revision rate was 8.4 percent.
At five years after surgery, revision rates were 6.1 percent for women with a 46mm diameter metal-on-metal implant, compared with just 1.6 percent for those with a 28mm metal-on-plastic implant.
In men aged 60 with metal-on-metal implants, revision rates were 3.2 percent for a 28mm head, jumping to 5.1 percent for a larger 52mm head.
DePuy, a subsidiary of Johnson & Johnson, issued a recall for its metal-on-metal hips in 2010. But the company took that step only after receiving hundreds of reports of early failure. An internal communication from 2005 showed that the company was aware of the problems.
Contact Lopez McHugh for a free case evaluation if you received a DePuy Orthopaedics hip implant and are experiencing side-effects.