A clinical study has found more than four in ten of patients fitted with the Birmingham Hip Modular Head (BHMH) possess “levels” of cobalt and chromium metals, from which the unit is made. There is also an indication of “a potential increased risk” from metal fragments released due to wear between the working parts.
Following the first notification of a potential fault in October 2012 and then a second in May 2013, legal proceedings were taken out against the manufacturers of the ‘metal on metal’ hip replacement in August 2013.
The latest warning from The Medicines & Healthcare Regulatory Agency (MHRA), the government regulator of medicines and medical devices in the UK, also includes data from January 2015 revealing that the unit has a failure rate of more than 10 per cent after six years.
The NHS has been advised by the National Institute for Health and Care Excellence (NICE), that only hip replacements with a failure rate of 0.5 per cent or less when checked each year should be used for implants. The new data suggests that the BHMH has a failure rate more than three times higher than is regarded as acceptable for use in the NHS when a follow up check is made after six years.
As a result, patients claimed to have suffered “adverse reactions” to the metal wear and the early failure of their BHMH hip head replacement. Those who needed surgery to remove the BHMH unit were also affected by long-term damage, which restricts their quality of life.
It is estimated that 700 people are presently pursuing claims against the manufacturers for allegedly faulty replacement hips, and doctors are recommended by the manufacturers to follow up patients implanted with the BHMH, where appropriate.
One in ten medical products which fail involve orthopaedic implants, such as a hip replacement, according to a survey by The Institution of Mechanical Engineers (IME), 2014.