Experts in the United Kingdom are so alarmed with the failure rate of metal-on-metal hip implants that they have stated that the devices should no longer be used. The British Hip Society, a group that represents surgeons who specialize in hip replacements, gave this warning in late February specifically about replacements with large diameter bearings.
The British Orthopedic Association reports that 5.5% of all large metal-on-metal implants need to be replaced within five years versus 2% for the plastic implants. In addition, research shows that when the large metal joints rub together, it sheds tiny shards of metal which leach out into the surrounding tissue and bloodstream. This causes painful soft tissue damage around the joint, destroys muscle and bone, among other growing evidence of health risks.
Most disturbing are the preliminary results from a study carried out by the UK researchers at the University of Bristol, which finds that patients with all-metal hip replacements may even be at risk of having the cells of their bladder genetically mutated, possibly causing bladder cancer itself.
It's advised by the UK's Medicines and Healthcare Products Regulatory agency for those patients who have high levels of metal ions from the metal-on-metal hips should get an MRI to test for damage around the joint.
DePuy Orthopedics, a manufacturer of metal-on-metal hip implants, has two devices that were recalled in 2010 due to an extremely high premature failure rate. The British Medical Journal reports that the company was aware of the fact that the product was linked to genotoxicity, a condition that causes cancer or mutation due to metal ions changing the DNA of the cells - and yet DePuy continued to actively market the device.