Most new products, from cheapo wristwatches to new cars, often come with manufacturers’ warranties. But that isn’t the case for most hip and knee implants, meaning that a growing number of Americans are having expensive devices put in their bodies without any written assurance from the manufacturers.

More than 4 million Americans currently have knee implants, and that number is expected to grow as life expectancy rates improve. In 2011 alone, there were 711,000 knee replacements performed. That same year, around 500,000 Americans received hip replacement implants. The combined annual demand for these two surgeries is expected to reach 4 million by 2030, and more than half of those patients will be under 65 years old, meaning they will likely be living with the implants for quite some time.

Yet, of the six major manufacturers of knee replacement implants — Biomet, DePuy, Smith & Nephew, Stryker, Wright, Zimmer — only one (Biomet) offers any sort of warranty, and that’s only on one partial knee implant model.

According to our coworkers at Consumers Union, between 2003 and 2013, these manufacturers recalled 709 different devices and components. During that same time period, these companies recalled 578 different recalls related to hip implants.

In both types of implant, the overwhelming majority of recalls were considered Class II recalls, which the FDA describes as “a situation in which use of or exposure to a violative product may cause temporary or medically reversible adverse health consequences or where the probability of serious adverse health consequences is remote.”

But more than 10% of all hip implant recalls were categorized as Class I, described by the FDA as “a situation in which there is a reasonable probability that the use of or exposure to a violative product will cause serious adverse health consequences or death.” Most of the Class I hip implant recalls were for products made by Stryker.

Some patients with metal-on-metal hip implants have experienced debilitating symptoms — including cardiomyopathy and neurological problems — from debris that flakes off the device over time. The FDA has thus proposed a more rigorous review process for metal-on-metal hip implants.

As we’ve mentioned in the past, FDA approval process for many new implanted devices is streamlined so that each new product need not undergo individual review it the manufacturer can demonstrate that the device is “substantially equivalent” to one that’s already on the market. This is similar to the process FDA uses for giving the go-ahead to cigarettes, which implies the agency holds cancer-causing products to the same standards as implanted medical devices.

Given that most new hip and knee implants are very similar to what’s already being used, the devices are fast-tracked without ever being tested to see if they are safe and effective.

In a 2012 poll, the overwhelming majority of American consumers said they believed in a rigorous review process for new devices, and Consumers Union was one of several patient safety groups that urged Congress to require more pre-market testing of implanted devices during last year’s reauthorization of the Medical Device User Fee Act. Alas, patient advocacy once again lost out to the deeper pockets of the well-heeled medical device industry lobbyists.

You may not care about people with implanted devices and you may say that warranties are unwarranted because many patients are not going out of pocket for these surgeries (or the seemingly inevitable replacement surgeries), but for every failed implant that hits the market, there is an impact on the average consumer.

Even if the patient isn’t paying for the surgery, someone is footing the bill — and it’s often quite a big bill. This is compounded each time there is a replacement, as it often costs more to remove and replace an implant than it did to put it in initially. Patients often end up in the hospital for a longer period of time following these later surgeries.

Consumers Union estimates that revisions to hip and knee replacements cost hundreds of millions of dollars a year. Insurance companies aren’t going to shrug that much money off, especially when it seems likely to increase in the coming decade.

“Patients have a right to know how long medical device manufacturers are willing to stand by their products,” said Lisa McGiffert, director of Consumers Union’s Safe Patient Project. “While patients may be told by their surgeon how long a device can be expected to last, they rarely get a guarantee in writing since most hip and knee implants do not come with a warranty.”

“Medical device companies claim that current law provides adequate protection for patients and that their implants are dependable and safe,” said McGiffert. “If that’s the case, they should have no objection to offering warranties to back up those claims. Patients and taxpayers shouldn’t be on the hook for the cost of replacing devices when they fail.”

CU has already written to the manufacturers, urging each to provide a 20-year warranty with their products. The letters also clarified that an ideal warranty would:
*Cover the full cost of replacing the flawed device, including the device, surgeon and hospital costs as well as related patient out-of-pocket costs.
*Establish a clear system for patients to use, including a toll-free phone line and a registration number to track the claims process, with physicians charging the device company, not the patient.
*Not eliminate the patient’s right to sue if they use a warranty.
*Provide the patient with a full explanation if a warranty claim is denied and an appeals process for denials.
*Not disqualify patients across the board if they have specific diseases or illnesses that are not related to the failure of the device.

For those who believe that manufacturers should include warranties with their implanted medical devices, the folks at CU’s Safer Patient project have put together this handy online form to let you voice your opinion to these companies’ chief executives.

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