The oversight of the development and introduction of new medical devices, and the evidence needed to start using them is much inferior to the evidence demanded for new drugs. This needs to change and the Metal on Metal story illustrates this well. The litigation alone is going to cost the earth…
Tens of thousands more patients with defective hip replacements will be called in for regular checks after it emerged that even those with no symptoms could be at risk.
All patients with metal-on-metal hips should have scans and blood tests to spot emerging problems, regulators said yesterday.
Surgeons say that by the time symptoms emerge it is sometimes impossible to replace damaged joints properly. They want to monitor hips for longer so that they can be replaced more easily, as further evidence shows that implants can fail more than a decade after they were put in.
Metal-on-metal hips were often used in younger patients as it was thought that they would last longer than plastic or ceramic implants. However, problems surfaced a decade ago when it became clear that the hips wore faster, shedding tiny metal particles into the joint. This can cause damage to bone and surrounding tissue, causing painful symptoms and irreversible harm in some cases.
Metal-on-metal hips are no longer implanted and the Medicines and Healthcare Products Regulatory Agency last issued guidance five years ago, saying people with the implants should see a doctor if they had pain, swelling near the joint or problems walking. People with some makes of hip were advised to have more regular surveillance.
Neil McGuire, clinical director of medical devices at the MHRA, said: “Although the majority of patients with these metal-on-metal devices have well-functioning hips, it is known some may develop soft tissue reactions. Clinical advice indicates patients will likely have the best outcomes if these problems are detected early, monitored and treated if necessary.”
Evidence has mounted that waiting too long could make it “almost impossible” to do a full repair, Dr McGuire said. “The information we’ve been working through does suggest that if people have emerging problems, if they are being followed up closely with appropriate imaging, you’re in a better position to decide if something needs to be done or not. We’re trying to avoid any patient getting to the point where they have to have a revision and the surgeon finds the job is more difficult.”
Checks could range from every year to once in seven years, depending on the type of device and symptoms. Replacing the hip should be considered if there are signs of problems on the scan, blood metal levels are rising, or if function is deteriorating, the guidance says.
Dr McGuire said it was also now clear that problems could emerge after many years, changing the calculation as the devices neared the end of their lives.