Remember that March 13 British medical journal article in The Lancet a few months back? We blogged about it here. The Cliffs Notes version is that The Lancet believes that metal-on-metal hip replacements are terrible, defective products and should not be used. Ever. They based this conclusion on a British National Joint Registry that tracks the patient outcome for these devices. The failure rates are too high—an average of 6.2% over five years, and even higher for women and larger implants. The safer alternative is ceramic hip implants.
There was another report around the same time by the British Medical Journal, How safe are metal-on-metal hip implants? (Read the box on page 4—How commercialism trumped safety). The article noted that the FDA considers all hip implants to be high-risk medical devices, meaning that new products cannot be fast-tracked to the marketplace. This article reported on the same hazards as The Lancet, in particular, toxic metal debris releasing into the body.
Johnson and Johnson strikes back against these articles in the latest issue of the British Medical Journal. DePuy’s International Clinical Director writes: While we respect the BMJ’s right to rigorously investigate issues, this article is unnecessarily alarmist and in a number of instances factually incorrect.
Johnson & Johnson defends, not so much on the basis that their product is safe, but on the basis that the risks of their product were widely known. The response discusses (1) adverse reactions to metal debris; (2) whether metal ion levels are as high as suggested by the British Medical Journal; (3) metal-on-metal hip implant cancer risks; and (4) corrosion of the taper (the part inserted into the leg bone). The one substantive “edit” is that the revision rate is actually 3% for a 5-year period after implant. It’s probably important to note that this number is at least partially based on studies performed by Johnson & Johnson/DePuy. They obviously have a commercial interest in the outcome, and as far as I know they haven’t shared their data. I can’t imagine that they are going to sway many doctors with their arguments, which are self-serving and devoid of any real evidence.
The author of the BMJ article quipped back that her study was “necessarily alarming.” Part of the problem is the process for getting medical devices like this to the market—in many cases, these new products piggy-back on older device approvals without the need for rigorous clinical studies. As a result, there is little data to work with until many years after the products are first released to the public.
Metal-on-metal hip implant injuries, including DePuy hip implants, include an early failure rate (necessitating a painful revision surgery), and even blood poisoning or inflammation because of metal toxicity. Both Smith & Nephew and Zimmer also make metal-on-metal hip implants. If you have one of these implants and are having problems with it, contact us at 1.800.553.8082, or online.