On January 17, 2013, the U.S. Food and Drug Administration (FDA) issued new safety information and recommendations to patients and health care professional regarding metal-on-metal hip implants. The FDA recognized that in addition to the general risks associated with the implantation of any hip device, metal-on-metal hips expose patients to an additional set of unique risks including “adverse local tissue reaction (ALTR),” “adverse reaction to metal debris (ARMD)” and increased metal ion levels in the bloodstream. The new recommendations encourage doctors to take a much more proactive approach in monitoring patients for potential complications, and apply to both total metal hip replacement systems and metal hip resurfacing systems.
The FDA recommends that orthopedic surgeons select a metal-on-metal device over other alternative systems available only if the benefits outweigh the possible risks. Doctors are urged to consider a patient’s age, sex, weight, diagnosis and activity level when considering possible risks. After surgery, the FDA recommends that doctors conduct physical examinations and routine radiographs every 1-2 years. Symptomatic patients or those with an increased risk for device complications should be monitored more closely. When additional imaging is needed, doctors are encouraged to utilize specialized diagnostic imaging test such as a MRI with metal artifact reduction or CT scans to assess and diagnose soft tissue damage. At this time, the FDA does not recommend routinely checking metal ion levels in the blood if the hip appears to be functioning properly and the patient does not report any complications. However, in patients experiencing complications, the FDA recommends that doctors consider monitoring serial metal ion levels. The FDA noted that it presently does not have enough scientific data to identify a specific metal ion level that produces adverse systemic effects.
On January 17, 2013, the FDA also issued a proposed rule requiring manufacturers of metal-on-metal total hip replacement systems to submit premarket approval (PMA) applications to the agency. The FDA commented that metal-on-metal hip replacement systems were evaluated under the 510(k) approval program. These devices were approved by the FDA based on representations from the manufacturer that the device was substantially similar in terms of safety and efficiency to devices already on the market.
Under the new proposed rule, manufacturers of metal-on-metal hip devices would be required to submit clinical data proving that the device is safe and effective in order to continue selling the device or obtain approval for a new device. If a company fails to provide the clinical data or the data fails to meet the FDA’s standards, the manufacturer would have to stop selling the hip device. According to agency officials, the rule will likely take a year to be finalized.