Metal hip implant patients need lifelong checks

Posted 29/02/2012

There have been numerous stories in the press recently surrounding the dangers associated with metal-on-metal hip replacements after investigations revealed that the rubbing between the ball and the cup can cause metal to break off, seeping into tissue and causing complications, such as inflammation and damage to muscle and bone.In 2010 the ASR all-metal hip device, manufactured by DePuy, was recalled following such investigations. However, another of DePuy’s hip devices, the Pinnacle is still widely being used today despite concerns that this device harbours the same problems as the ASR.A joint investigation undertaken by BBC News Night and the British Medical Journal has revealed internal documents pertaining to the dangers associated with the ASR and the Pinnacle devices dating as far back as 2005 and warning of the metal debris being harmful to patients. It was reported that design changes were made to the all-metal devices by without trials being conducted to test the safety and effectiveness of these changes. It is this design change that experts say is likely to be “responsible for the release of high levels of toxic metals into the body”.Following these investigations new advice was published by The Medicines and Healthcare Regulatory Authority (MHRA) informing medical practitioners of the monitoring requirements of patient with such hip replacements. Those patients who have undergone large head metal-on-metal hip replacements should now be monitored annually for the lifetime of the hip replacement, with blood tests being carried out to check for increased levels of metal and an MRI scan if ion levels are seen to be rising. This is a substantial change in comparison to previous advice which recommended monitoring for a minimum of five years post-operation.Samantha Collins, a medical injury solicitor at Ashtons Legal comments “I am pleased to see the MHRA have increased the level of monitoring for patients who have undergone metal-on-metal hip replacements. However, this is still not enough. There are many patients out there who have undergone metal-on-metal hip replacements who will suffer years of worry. These patients need to be advised individually of the effects of the metal-on-metal hip devices to allay some of these fears and provided with choices regarding the best way forward in terms of their future health. Since banning the ASR hip implant, regulators have been slow to act against other metal-on-metal implants which shed metal particles into surrounding tissue. An investigation needs to be launched into all types of metal-on-metal hip implants so we understand exactly the effects of placing these devices in the human body. Drugs would not be given to a patient without being scrutinized and tested for years; how is it appropriate to place an artificial implant into a human body without this same rigorous testing?”