The National Joint Registry for England and Wales (NJR), the largest registry in the world to track orthopedic devices, has reported more bad news about metal-on-metal hip implants. The latest NJR report, released last week, spells trouble for recipients of many kinds of all-metal hips, but is especially ominous for patients who received one of the two DePuy ASR hip implants that the manufacturer recalled last August.
According to the new report, metal-on-metal hip implants, which were intended to be more durable and longer lasting than traditional metal and plastic implants, are failing at increasingly higher rates. Failure rates are the worst for DePuy’s ASR XL Acetabular System and ASR Hip Resurfacing System, which NJR data found failed 17 percent of the time in patients who received the implant five years ago. For patients who received one of the recalled DePuy hip devices six years ago, 29 percent have had a revision surgery to remove the DePuy device.
Data pulled from the same registry in early 2010 found 12 percent of the ASR Resurfacing systems and 13 percent of the ASR XL systems failed within 5 years. The findings mirrored concerns about the DePuy implants that first became apparent in Australia’s much smaller orthopedic joint registry system. This preliminary data prompted the recall of the devices in August 2010, after they had been implanted in about 93,000 patients worldwide.
Unfortunately, no single orthopedic joint registry exists in the United States, where the majority of the DePuy ASR XL devices were implanted in patients. However, the U.S. Food and Drug Administration’s data shows a sudden surge in the number of DePuy ASR XL complaints, which correlates to the escalating failure rates in the U.K.
A New York Times analysis of FDA data found that the agency received more reports involving DePuy’s all-metal hip replacements in the first six months of 2011 than it had in the previous four years combined.
Many patients who have had an all-metal DePuy device have reported symptoms indicative of metal poisoning, caused when friction between the metal parts releases particles of cobalt and chromium unto the blood and tissue. The same degeneration of the metal parts is believed to be reason why the DePuy devices fail prematurely. Some of the most commonly reported symptoms of a failed hip implant include constant paint, diminished mobility, and bone fractures.