MoM hip replacements potentially causing long-lasting injuries

All Metal-on-Metal (MoM) hip replacement patients are being recalled for advice and investigation in the U.K. The Medicines and Healthcare products Regulatory Agency (MHRA) has recently issued an updated medical device alert on 29^th June 2017.

It’s estimated that 49,000 patients in the U.K. were given the MoM implants (with width of 36mm or above). The NHS notes that around 3,387 surgeries in 2010 used the 36mm (or above) MoM implants.

The issue with the MoM hip replacements

The MHRA along with its independent MoM Expert Advisory Group has continually monitored the performance of those who have received MoM hip joints which may react with soft tissue. The majority of patients who have MoM hip replacements are reported to have well-functioning hips. However, there are huge concerns that some MoM hip replacements are causing the wearing down of soft tissue which is associated with the MoM articulations.

Data from the 13^th Annual Report of the National Joint Registry of England, Wales, Northern Ireland and the Isle of Man (2016) support these assertions. Within the report they note that the particulate debris adversely reacts to patient’s soft tissue in some cases, and can cause serious lifelong injuries.

Experts’ advice

The MHRA’s appointed clinical orthopaedic experts also support these assertions. They state that soft tissue necrosis may occur, and the devices also have the ability to destroy the muscles, skin, and underlying tissue. Worryingly, not all patients whose devices have failed will show symptoms. Orthopaedic experts believe that early detection of problems should allow patients to have a quicker recovery if they’re having problems.

There’s no universally agreed threshold for whether blood metal levels necessitate revision straight away. The decisions to revise the MoM hip replacement are also influenced by patient factors, blood metal levels, imaging findings and implant type and position. It’s also patient specific, so other factors may need to be considered when looking at blood metal levels.

MHRA’s advice

This safety alert replaces the ones previously published before i.e. in 2012, 2013 and 2015.

In its medical device alert, the MHRA suggests two actions that need to be taken:

These actions must be complete by 27^th July 2017.

Long-lasting impact?

It’s critical that this information is passed on as the likelihood of injury caused can be high for some.

The NHS has also warned about the hip implant stating that all metal devices have been found to wear down at an ‘accelerated rate’ in some patients.

With these patients it could potentially damage and deteriorate the bone and issue around the hip. They also reiterate the concern that leaked traces of metal could enter into the bloodstream.

If MoM hip implant patients suffer any of the following symptoms its advised to seek medical advice:

The symptoms don’t necessarily indicate that the hip implant is defective, but such symptoms may be a cause for concern.

The previous advice on the same implant suggests that patients should be monitored every year for at least 5 years (BBC News suggest that these patients should be monitored for life).

The issue isn’t just contained in the U.K., both the U.S. and Canada have raised its concerns with these hip replacements.