Health Canada has issued a new warning to patients and doctors about the possible complications associated with metal-on-metal hip replacements, and is alerting patients there about warning signs of a malfunctioning all-metal hip implant. The Health Canada warning comes amid a growing number of reports worldwide regarding implant loosening, as well as significant soft tissue reactions thought to be the result of increased levels of cobalt and chromium ions shed by metal-on-metal hip implants.
According to the agency, metal-on-metal hip replacement devices make up just 10% of the hip implants used in Canada. Health Canada is advising doctors that patients who receive metal-on-metal hip implants should be followed annually for five years and then afterwards on a schedule that meets the “locally agreed practice.” Patients at highest risk of developing metal-on-metal hip implant complications, including women, physically active patients, patients who are severely overweight, or those with implants in both hips, should be followed more closely.
Health Canada also warned that metal-on-metal hip implants patients experiencing the following symptoms more than 3 months post-op should be assessed:
- Pain in the groin, hip or leg
- Swelling at or near the hip joint
- Onset of a limp or change in walking ability
- Limited range of motion
Patients who experience these symptoms should undergo MRIs and other imaging tests, and possibly whole blood or serum tests for cobalt and chromium metal ion levels to determine if their implant is failing.
Metal-on-Metal Hip Implant Controversy
Metal-on-metal hip implants have been the subject of safety concerns since the August 2010 global recall of DePuy Orthopaedic’s ASR hip implants. In May of last year, the U.S. Food & Drug Administration (FDA) asked 21 makers of metal-on-metal hip implants to conduct safety studies of their devices. In June, the agency will convene a panel of outside advisers to discuss the problems related to metal-on-metal hip replacements.
Since the DePuy ASR hip implant recall, several studies, including recent reports in The Lancet and the British Medical Journal, have linked metal-on-metal hip implants to premature failure. The authors of The Lancet study went so far as to call for an end to the use of the devices, while the British Medical Journal report warned that hundreds of thousands of people around the world may have been exposed to dangerously high levels of toxic and potentially cancer-causing metals from failing metal-on-metal hip implants.
Metal-on-Metal Hip Implant Lawsuits
The DePuy ASR hip implant recall also spawned a wave of litigation against the makers of metal-on-metal hip replacement devices. More than 4,200 lawsuits are pending against DePuy Orthopaedics and its parent, Johnson & Johnson, in the DePuy ASR hip implant multidistrict litigation now underway in the U.S. District Court for the District of Northern Ohio. Another 2,000 DePuy ASR hip implant lawsuits are pending in various state courts around the country. Bellwether trails in the federal litigation are expected to start sometime early next year, while the first state lawsuits are headed to trial in Nevada and Maryland later this year.
In February, a multidistrict litigation was established in the U.S. District Court for the Northern District of Georgia for lawsuits involving the all-metal Wright Conserve Hip Replacement System. Claims involving a metal-on-metal version of DePuy’s Pinnacle hip implant have been consolidated in a multidistrict litigation in Texas. Several lawsuits are also pending in the U.S. over Biomet metal-on-metal hip implants.