Hi Joe, Not Colleen here, but a recipient of metal-on-metal (MOM) implants 17 years ago, who had them replaced 11 years ago.

MOM hip implants were developed and approved in Europe around 2000, designed especially for use in younger & more active patients on the theory that the very hard (chromium & cobalt) metals would provide longer wear then the traditional metal or ceramic ball/poly cup liner models in common use. They were approved for use in the US around 2004-5 based on the European approvals, which has been a pretty common practice.

In 2006-2007, surgeons in Europe and the UK began seeing a much higher than predicted rate of failures of these implants, but continued using them and they were slow to share their experience in the ortho world. As a result, surgeons around the world continued to use them, and after a short time the US began to see excess failures as well.

Lawsuits ensued. In 2010 the manufacturers and distributors issued a caution to all surgeons that anyone with MOM implants who was having issues of pain, instability or failure needed to be screened for metallosis and implant failure.

Around 2010 the FDA stepped in to study the issue, and by 2011 the MOM implants stopped being used. As of 2012 FDA requires additional PMA (Pre Market Authorization) of any MOM devices being used or proposed.

As of today, there are no MOM total hip replacement devices approved, or requesting approval. There are just two MOM hip resurfacing devices (a much less invasive surgery) that went through approval and are on the market.

So, there are many people (in the thousands) who still have MOM hips, many without issue. There are also some who are now experiencing issues & getting them replaced. The reasons for why some work fine & others fail are probably varied, but one that is known is that they are much more "picky" about placement - with the polymer liner, there is some tolerance in acetabular cup positioning, with the harder metals, perfect placement was crucial.

My surgeon really thought he was doing the "right thing" to give me a longer-lasting joint, but as time proved, newer is not always better!

Fortunately, it did lead to a valuable policy change in the approval of devices by the FDA.
Sue