Why do patients with all-metal hip implants experience more pain? The DePuy ASR and Pinnacle hip implants manufactured by American healthcare colossus Johnson & Johnson have caused great controversy in light of their remarkably high failure rates – which led to a worldwide recall of approximately 93,000 ASR implants back in 2010. Concern has been growing over the health problems caused by the metal components of the implants wearing down. However a new study from the Orthopaedic Biomechanics at the Hospital for Special Surgery (HSS) suggests that it is in fact tissue damage that causes patients the most pain.

Although the all-metal implants were originally marketed as more durable alternatives to similar ceramic devices available, they have been found to fail prematurely at an alarming rate – requiring many patients to have revision surgeries to replace the defective devices. The HSS study looked at 50 patients whose hip implant revision surgery was scheduled in light of unexplained pain, against 48 other patients whose second hip replacement operation became necessary as a result of infection, bone fracture, misalignment or loosening of the implant.

Scientists looked for evidence that tissue had been damaged by metallic shards from the implant. The severity of the damage caused was then given a score between 1 and 10. They discovered that 3 in every 5 patients with unexplained pain scored at least 5 on the tissue damage scale and that over 1 in 10 across both categories suffered from metallic debris collecting in their soft tissues. Amongst those with unexplained pain, there were 10 times as many with high grade tissue damage as in the other category.

Despite being warned as early as 2005 that there were serious problems with the ASR devices, DePuy did not recall the products until 2010. The company is now facing 10,750 lawsuits as a result and damages payouts are expected to cost parent company Johnson & Johnson billions of dollars.

Furthermore, according to a FDA funded study, it appears that women are at a greater risk of experiencing premature hip implant failure than men. The study comes at a controversial time for hip implant manufacturers with companies such as DePuy and Stryker having issued recalls of metal-on-metal hip devices amid reports of high failure rates – and with DePuy, in particular, already having lost one of the test cases arising out of the hip replacement recall scandal.

The FDA funded study drew upon data from 35,000 hip replacement patients and revealed a series of interesting findings. Most strikingly, women are 29% more likely to suffer from a failed implant than men, requiring many more women to go through the pain and trauma of a follow-up or ‘revision’ surgery in order to have their hip implant removed and replaced.

The study also found that more men receive all-metal hip devices such as the DePuy ASR implants which were subject to a global recall in 2010. Whilst the gender comparisons are interesting, there is little explanation as to why such differences exist.

Recipients of metal-on-metal hip implants in particular have complained of a whole range of health problems in recent years. Joint dislocations, bone loss, metallosis, implant loosening and tissue damage have all been cited in various lawsuits. One of the biggest concerns is metallosis, which is a severe form of metal poisoning thought to be caused by cobalt and chromium fragments flecking off the hip device as metal components grind together; a particular problem in ASR implants.

Following the high number of complaints, the FDA issued new guidelines for all-metal implants at the start of 2013. Doctors have been told to avoid the devices where possible and manufacturers will need to carry out much more extensive testing to demonstrate that new products meet the required safety standards.

Despite being warned as early as 2005 that there were serious problems with the ASR devices, DePuy did not recall the products until 2010. The company is now facing 10,750 lawsuits as a result and damages payouts are expected to cost parent company Johnson & Johnson billions of dollars.

If you have been the victim of the hip replacement recall scandal in England and Wales, then you could be entitled to make a claim for medical negligence compensation in respect of your pain and suffering.

Tim Bishop, senior partner of Bonallack and Bishop – Solicitors with a specialist team of medical negligence experts. For more information about how to claim medical negligence compensation, visit the website at http://www.themedicalnegligencesolicitor.co.uk or phone their medical negligence solicitors directly on 01722 422300.