A recent report by the National Joint Registry for England and Wales brings more bad news for patients who have received DePuy metal-on-metal hip replacements. According to the report, the DePuy metal-on-metal device has failed in over one-third of the British patients who’d received it. While the study does not reflect the failure rates for U.S. patients, it does report on data that we do not collect in the U.S. and therefore can be a useful indicator of potential failure rates in the U.S.
Metal-on-metal artificial hips were designed to last longer than their plastic counterparts, yet the medical advances in this case might have done more harm than good. The British report clearly shows that these all metal hip devices are failing at a much faster rate than artificial hips composed of alternate materials, including a combination of metal and plastic. And while the British report is not the first of its kind, its findings collaborates earlier studies which demonstrated that all metal hips are not as durable as the other options.
The main theory on why the metal-on-metal hip devices fail at a faster rate centers on the fact that every component is made of metal. While it would seem that metal would be more durable than plastic, in reality the all metal construction has led to other unexpected problems. As the metal hip socket rubs against the metal hip joint, the movement seems to release tiny particles of the various metals. This debris is released into the surrounding hip cavity and not only causes crippling injuries to the person, but also diminishes the effectiveness of the metal artificial hip. Therefore, it is the design defect of the all metal construction that is leading to the increased failure rate of metal-on-metal hip devices.