Lawsuits involving Wright Conserve metal-on-metal hip implant devices have been consolidated in a multidistrict litigation (MDL) in the U.S. District Court for the Northern District of Georgia. The Wright Conserve hip implant lawsuit MDL is the third to be established by the U.S. Judicial Panel on Multidistrict Litigation (JPML) involving metal-on-metal hip implant devices.
The Wright Conserve hip-replacement system includes the Conserve Femoral Surface Replacement, the Conserve Plus Total Resurfacing Hip System, the Conserve Total A-Class Advanced Metal and the Conserve Total Hip System. Like other metal-on-metal hip implant devices currently on the market, the Wright Conserve hip replacements were approved via the U.S. Food & Drug Administration’s (FDA) 510(k) approval protocols, which do not require human testing if a device is shown to be “substantially equivalent” to a product already on the market.
The claims pending in the Wright Conserve hip implant MDL center on the all-metal design of the devices, and allege they are prone to the generation of high levels of metal debris, cause metallosis in the surrounding tissue and/or fail early (including loosening of the acetabular cup). According to the JPML’s Transfer Order, there are at least 22 Wright Conserve hip implant lawsuits pending in various federal courts.
MDLs that involve similar claims are currently pending against DePuy Orthopaedics in the U.S. District Court, Northern District of Ohio and U.S. District Court, Northern District of Texas. The Ohio litigation encompasses lawsuits naming the DePuy ASR hip implant, which was recalled by the company in August 2010. An all-metal version of DePuy’s Pinnacle Hip Implant System is named in the Texas MDL.
The growing litigation surrounding all-metal hip implants is being fueled by a mounting body of evidence linking the devices to serious health problems, including premature failure, cobaltism and metallosis. Last May, the U.S. Food & Drug Administration (FDA) directed 21 companies, including DePuy and Wright Medical, which market all-metal hip replacement devices to conduct post-market studies of their products to determine if they were shedding dangerous amounts of metallic debris in patients. Last week, The Lancet published a study conducted by University of Bristol researchers who found that people with metal-on-metal hip implants were twice as likely to experience early failure of their device compared to those fitted with other types of implants. The authors of the study asserted the devices should no longer be used. Late last month, the British Medical Journal revealed that metal-on-metal hip implant manufacturers were aware of mounting evidence linking metal-on-metal hip replacement devices to serious, long-term health consequences, but for years failed to warn the public about these dangers.
In the U.K., the Medicines and Healthcare Products Regulatory Agency (MHRA) announced that blood tests should be conducted yearly to check cobalt and chromium blood levels in some all-metal hip implant recipients, those with bearings of 36 mm or above, as well as MRIs for any patient who does exhibit high metal ion levels. The British Hip Society recently advised that larger metal hip implants not be used at all in total hip replacement surgery.
The controversy surrounding metal-on-metal hip implants is apparently causing doctors to turn to alternatives. As we reported previously, at the height of their popularity the devices were once used in about one-third of all total hip procedures. Now, they make up less than 5 percent.
