British doctors have published evidence of an “unacceptably high revision rate” for a hip implant that has been the subject of a multi-million pound US lawsuit.
Almost 12,000 Britons have received the Pinnacle metal-on-metal hip implant made by DePuy, part of Johnson & Johnson, according to official joint registry data.
Now researchers say they have operated on patients with “black tissue” caused by “high levels of chromium and cobalt” and that patients have suffered pain.
DePuy was forced to recall a different implant (the ASR) in 2010 after the devices were linked to muscle and bone damage and neurological issues.
In March this year, Johnson & Johnson was ordered by a Texas federal jury to pay around $US500 million ($A656 million) to five people who said they were injured by the Pinnacle metal-on-metal hip implants.
The jury decided the Pinnacle hips were defective and that DePuy had failed to warn the public about their risks.
Johnson & Johnson has said it will appeal that verdict. Thousands more people have launched action against the company.
Dr David Langton, from the University Hospital of North Tees, who led the latest study, said his team had told DePuy in the UK, and a healthcare regulator of problems with the Pinnacle over several years.
“These Pinnacle implants were advised for younger patients who were very active,” Dr Langton said.
“We have found that they fail at a higher rate than conventional ones but they fail in a much nastier way.
“You get very high levels of chromium and cobalt around the hip and that can go into the bloodstream. There can be black metal-stained tissue.”
Dr Langton said his team believed up to 20,000 people in the UK had received the implants.
The study, published in the journal BMJ Open, found the Pinnacle metal-on-metal implants manufactured and implanted since 2006 were more prone to failure.
The team looked specifically at the long-term performance of the 36mm Pinnacle metal-on-metal hip.