Doctors have known for several years that some hip devices, in which both the ball and cup are made of metal, were failing at faster rates than other hip implants. Now, new research is confirming this information and claiming that the problem can cause trouble for many years to come, even after removal.
“This is a serious problem in the USA,” said Mathias Bostrom, an orthopedic surgeon at the Hospital for Special Surgery in New York City. “Some implants have a worse record than others, but almost all the metal-on-metal implants have issues.”
Damage to the body occurs, Bostrom said, when the implant pieces move against each other and metal debris breaks off, lodging in nearby soft tissue and bone and entering the blood. Inflammation and tissue death can occur around the joint, and problems affecting the heart and nervous system, although rare, can develop from toxins entering the blood, the FDA said.
But, this may not be the worst, according to the U.K.’s Telegraph newspaper, a medical study underway is expected to reveal that side effects of metal-on-metal hip replacements can cause genetic damage, which could lead to an increased risk of cancer.
The study to be presented next month at the British Hip Society conference will include findings that suggest the metal particles released by the grinding of metal-on-metal hip replacements could cause chromosomal changes, which may lead to kidney cancer and bladder cancer.
Last May, the U.S. Food & Drug Administration (FDA) directed 21 makers of all-metal hip implants, to conduct post-market studies of their products to determine if they were shedding dangerous amounts of metallic debris in patients.
The FDA’s order came after the August 2010 worldwide recall of DePuy Orthopaedics’ all-metal ASR Hip Resurfacing System and the DePuy ASR Acetabular System, after data from the National Joint Registry of England and Wales showed that 1 out of every 8 patients (12%-13%) who had received the devices had to undergo revision surgery within five years of receiving it.
DePuy, a division of Johnson & Johnson, currently faces more than 3,500 U.S. lawsuits over its defective ASR hip implants. Another 900 lawsuits are pending in the U.S. over an all-metal version of its Pinnacle hip replacement device.
The US Drug Watchdog says, “Because many individuals, who received a DePuy ASR hip implant do not want to go through a painful hip replacement surgery, also called revision surgery, they do not complain. Because of this, we are strongly encouraging family members or loved ones of anyone receiving a hip implant between 2005 and early 2010 to ask if it was a DePuy ASR hip implant.”
They say, “What worries us is the fact that the DePuy ASR hip implant was sold as the right hip implant for younger, or older adults, who wanted to maintain an active, or athletic lifestyle.” The group says, “We could have tens of thousands of DePuy hip implant victims in the US, and because of age, or not wanting to go through a hip replacement revision surgery, they say nothing. Nothing is more important to us than trying to get them some help.”