Most people assume that the FDA fully vets all new medical devices including knee replacement implants. They assume that they have been tested and determined to be safe and effective before they are placed on the market and sold to the American people.
Unfortunately that is not the case.
The 510K PreMarket Approval Process
The 510K as it is called allows companies to rapidly get approval for a knee replacement implant by providing evidence of its’ similarity to another device currently being marketed.
According to Drug Safety News, “this fast-track process is often abused by deceitful companies who want to skip the many complex clinical trials they are required to plan before a product is approved. The 510(k) regulatory pathway is, in fact, used to bypass the long testing phases whenever a medical device is “substantially equivalent” to others already found on the market.”
The bottom line is that new design or composition changes in knee replacement implants are in reality tested on you the unwary consumer who has no idea how the process works.
In many countries voluntary registries which track data on knee replacement surgeries are used to identify when an implant might be trending toward failure or harm. This data is closely monitored when a trend is identified and it is usually up to the implant manufacturer to initiate the recall.
However in the United States, the registry data is still very small compared to the number of devices that are implanted. So a recall is usually initiated through lawsuits or public outcry. In rare cases the FDA will raise concerns or request a recall from the manufacturer.
This after the fact surveillance while helpful to all the stakeholders is a poor substitute for real assurance about safety and reliability. I doubt potential knee replacement candidates will sleep any better knowing the registry exists.
Between 2003 and 2013 there were 709 recalls of devices or components of knee replacement implants. Buyers beware.
Of course there is always a balance between, the cost of doing clinical trials and the advantages of getting devices to the market quickly that can help people. Except we are not talking about a miracle drug or a tweaked design capable of making a quantum leap in knee replacement outcomes or user experience.
The Last Fly in the Ointment
And finally the last best-kept secret is the amount of money that some surgeons make in the form of consulting fees from the implant companies. For a new design to make money, some surgeons need to start using it. If a surgeon is not convinced that a major improvement is being gained through the adoption of this new technology, why not stick with the devil he knows? A little bit of cash as a consultant can solve that problem.
Are you starting to think of a few more questions you would like to ask your surgeon before you agree to have your knee replaced? I hope so.