The FDA is providing updated safety information about metal-on-metal hip prostheses, including recommendations to patients and health care providers. This new information is based on the FDA’s current assessment of metal-on-metal hip implants, including the benefits and risks, the evaluation of the published literature, and the results of the June 2012 Orthopaedic and Rehabilitation Devices Advisory Panel meeting.
It’s been a while in the making, but this comprehensive communique on the state of play and the management of the metal-on-metal hip situation is likely to be welcomed by healthcare professionals and patients alike, especially prospective patients for whom these prostheses are being advocated.
The document can be found here and includes recommendations for surgeons, most notably about the decision to select a metal-on-metal hip system in the first place, given the balance of risk factors. It singles out younger males with larger femoral heads as being those most likely to benefit from this type of implant.
For those people already implanted with metal-on-metal hip prostheses with all their attendant issues identified over the past two years, the agency provides more guidance, building on that which is already out there. On the thorny issue of implant wear, the document goes on to discuss metal ion levels and, while it recognises that implantees have sometimes demonstrated raised levels of certain metal ions in their blood, thought to be symptomatic of the implant wear condition we’ve heard so much about, it is not directly linking ion level to a need for revision. Indeed, on the subject of implant revision it is also pretty guarded, noting that in cases where tissue damage exists, a revision procedure needs careful risk assessment before being undertaken.
One final observation is that, as of yesterday, Jan 17 2013, metal-on-metal hips now require PMA regulatory approval and can no longer go down the 510(k) clearance process with its lower burden of clinical evidence. The order making this happen can be found here.