Metal-On-Metal Hip Implants: Why Does FDA Guidance on Metal Ion Testing and Imaging Exclude Asymptomatic Patients?
New metal-on-metal hip implant guidance issued the U.S. Food & Drug Administration (FDA) may have some all-metal hip implant recipients confused, especially if they are aware of last year’s Stryker hip recall for Rejuvenate and ABG II Modular-Neck hip stems. While the FDA says it does not believe there is a clear need to routinely perform soft tissue imaging or blood tests on asymptomatic patients, Stryker Orthopaedics has explicitly advised both for patients impacted by the recent Stryker hip recall, even in the absence of symptoms.
Metal-on-Metal Hip Replacement Complications
According to a recent New York Times report, metal-on-metal hip implants, in which the ball and cup are made from chromium-cobalt alloy, have been fitted in more than 500,000 U.S. patients. Most metal-on-metal hip implants were approved via the FDA’s 510(k) approval process, which does not require a device to undergo human clinical trials if a manufacturer can demonstrate that it is substantially equivalent to a previously FDA-approved product.
Now it has become apparent that metal-on-metal hip replacements – which should last 15 years or so – are failing early in a high number of patients. As a result, thousands of patients have been forced to undergo painful and costly operations to replace the devices. There is also growing evidence that the metal particles shed from all-metal hip implants can damage surrounding tissue and bone and lead to a reaction called metallosis that has the potential to leave some victims disabled.
Problems with metal-on-metal hip implants first became apparent in 2010, when DePuy Orthopaedics, a division of Johnson & Johnson, recalled 93,000 ASR hip implants worldwide. The DePuy ASR hip recall was issued after data indicated the all-metal devices were failing in more than 12% of patients within five years of implantation. The FDA launched a safety review of metal hips in February 2011, and last summer, one of its advisory panels concluded that there were few, if any, reasons to continue using metal-on-metal hip implants.
On January 17th, the FDA issued new guidance regarding the follow-up of patients with all-metal hips. Among other things, the agency advised doctors to consider metal ion testing and soft tissue imaging if patients are experiencing symptoms of hip implant failure. While the agency recommended that asymptomatic patients undergo periodic (typically every 1 to 2 years) examinations and routine radiographs, it did not advise routine blood ion testing or other soft tissue imaging for patients whose hips appear to be functioning normally.
In addition to the guidance announced last week, the FDA issued a proposed order requiring manufacturers of metal-on-metal total hip replacement systems to submit premarket approval (PMA) applications. The proposal would make such devices ineligible for 510(k) clearances.
Stryker Hip Recall Recommendations
Last July, Stryker recalled some 20,000 Rejuvenate and ABG Modular-Neck hip stems. Although the Stryker hip recall did not involve a metal-on-metal hip implant, the company warned that fretting and corrosion of the metal components at the modular neck junction could cause pain, swelling and adverse local tissue reactions similar to the type seen with metal-on-metal hip implants. A report commissioned by Stryker and published just months before the Stryker hip recall was announced warned that such reactions could include “premature failure due to osteolysis, aseptic loosening and in some instances a devastating pseudotumor formation.”
Earlier this month, Stryker issued an update for the Rejuvenate and ABG II recall, and advised that all patient fitted with the components undergo blood tests for metal ion levels, as well as cross section imaging, even if they are not experiencing symptoms of a failing hip implant. The company is also advising that repeat follow-up examination, such as blood work and cross section imaging, should be considered for all patients with Stryker Rejuvenate and ABG II hip stems, even in the presence of normal initial finding.
According to the recall update, Stryker has received reports of patients with mild or no symptoms that have tested positive for elevated metal ion levels or been diagnosed with adverse local tissue reaction. Considering that similar complications are being seen in metal-on-metal hip implant patients, it does seem strange that the FDA’s recommendations differ so significantly from Stryker’s guidance.
Metal-on-Metal Hip Implants Lawsuits
Bernstein Liebhard LLP is actively filing lawsuits in the federal DePuy ASR hip litigation underway in U.S. District Court, Northern District of Ohio, as well as the DePuy Pinnacle hip litigation now proceeding in the U.S. District Court, Northern District of Texas. The firm is also offering free legal consultations to individuals injured by other metal hip implants, including:
- Biomet Magnum M2a hip replacement
- Wright Profemur and Conserve hip systems
- Stryker Rejuvenate and ABG II modular-neck stems
If you suffered complications or had revision surgery because of a defective metal hip implant, please contact Bernstein Liebhard LLP to discuss the legal options available to you. For more information, please call 1-877-779-1414.