A metal-on-metal hip implant. Copyright Corin.

Imagine you are a patient considering whether to have an artificial joint surgically inserted to relieve your debilitating hip pain. The orthopaedic surgeon provides you with a pamphlet from the implant manufacturer, which says that the device is guaranteed to be free of defects for one year. You also speak to a sales representative from the company who assures you that your new hip is “guaranteed to last at least ten years.” Is this a realistic scenario?

It transpires that none of the major orthopaedic implant manufacturers — DePuy, Smith & Nephew, Stryker, Wright Medical, Zimmer — offers a warranty to protect patients if the implant fails and needs to be replaced. They argue, probably with some justification, that the longevity of an implanted hip joint depends on factors beyond their control, including the patient’s weight, the surgeon’s skill and whether the patient followed post-operative guidelines on physical activity. However, there are certainly cases where failure can result from a defect in the implant materials or, as in the case of metal-on-metal hip implants, a poor design.

A failed hip joint awaiting revision. Copyright NHS.

The USA is renowned for litigation and American consumers are now starting to flex their collective muscles. The Consumers Union has recently challenged the manufacturers of hip and knee implants to provide warranties to have a defective device replaced at no cost. Lisa McGiffert, director of the Safe Patient Project, has said: “Patients have a right to know how long medical device manufacturers are willing to stand by their products.”

Consumers Union has just sent letters to all the manufacturers, urging them to provide a 20-year warranty, including: (1) the full cost of replacing the flawed implant (device, surgeon and hospital costs); (2) a clear system for making the claim; (3) does not eliminate a patient’s right to sue; (4) provides full explanation if a claim is denied; and (5) does not disqualify a patient who has a disease unrelated to the device’s failure.

While it seems highly unlikely that the companies will comply with these recommendations, some of which — like the 20-year warranty period — are unrealistic, there are some actions manufacturers can take to mitigate the risk of a failed implant. First, they can take out insurance with a company like Medmarc; and second, instead of hiding behind their FDA certification, they can place in the public domain all the evidence to show that their implants are both safe and effective. These would be steps in the right direction.