BMJ Reveals Shocking Facts About Metal-on-Metal Hip Implant DebacleFeb 29, 2012 | Parker Waichman LLP
A shocking investigative report published in the British Medical Journal has slammed the regulatory response to the growing problems surrounding metal-on-metal hip implants. According to the report, tens of thousands of people from around the world could face serious health consequences from toxic metal, thanks to a slow response by the U.S. Food & Drug Administration (FDA) and other medical device regulators.
The BMJ article points out that the toxic effects of cobalt and chromium ions have been known for decades. As we've reported previously, when cobalt and chromium ions shed from metal-on-metal hip implants, they can damage the surrounding tissue and bone, leaving patients permanently disabled. According to the BMJ investigation, which was a joint venture between the medical journal and the BBC, those ions can also leach into the blood stream, make their way to bodily organs, and possibly even cause chromosomal changes and cancer.
Metal-on-metal hip implants include DePuy Orthopaedics’ ASR Hip Resurfacing System and the DePuy ASR Acetabular Hip Implant System, which were recalled in 2010 because of an unusually high premature failure rate. However, according to the British Medical Journal, evidence that these hip implants were problematic were surfacing years before the devices were recalled. In 2005, for example, an internal DePuy memo voiced concerns that the implants could be linked to the development of cancer:
"In addition to inducing potential changes in immune function, there has been concern for some time that wear debris may be carcinogenic. The mechanism is not known and only 24 local malignancies have been reported in patients with joint replacements. Also worrying is the possibility of distant effects. One study suggested a threefold risk of lymphoma and leukemia 10 years after joint replacement. "
Regulators in the U.S. and Britain were also slow to respond to the growing crisis. Before the ASR hip implant recall, U.K.’s Medicines and Healthcare Regulatory Authority's (MHRA) only response to the growing crisis was to appoint a committee that included company representatives and several consultants to decide the fate of metal on metal hips. While committee concluded that patients should be told about the risks, no alert was issued to surgeons or patients. The agency also downplayed the implant's risk, stating that the majority of the patients with the devices "have well-functioning hips and are thought to be at low risk of developing serious problems.”
Both regulators overseas and in the U.S. also somehow missed that companies were making design modifications to these devices without conducting clinical trials of their safety and efficacy. Some experts believe these design changes contributed to the safety issues now associated with metal-on-metal hip implants.