Showing posts with label metal-on-metal. Show all posts
Showing posts with label metal-on-metal. Show all posts
Friday, February 28, 2014
Thursday, August 1, 2013
FAILED Hip Implants prompt FDA study.
Posted: 25 July
2013
By Alexander Gaffney, RF News Editor FiDA Highlight
One of the largest medical
device scandals in the last decade has involved
metal-on-metal hip implants,
so-named because of the metal (usually chromium)
attachment that attaches a
leg to a metal socket.
In the wake of their failures, the
US Food and Drug Administration (FDA) moved to examine its regulatory
processes, eventually deciding
to require premarket approval (PMA) applications for all such implants.
But now evidence has emerged that the agency still has further questions about
what more it could have done to prevent the devices from ever having reached
the market.
Background
Medical devices are a relatively
recent addition to FDA's regulatory authority, with FDA only receiving the
authority to vigorously regulate them in 1976 under the Medical Device
Amendments. Because some medical devices were already marketed at that
time, FDA classified them all as class III, high-risk medical devices until it
could review and classify them properly.
Some of those devices went on to
serve as predicates for 510(k) premarket notification applications, which
claimed that they were substantially equivalent to already-approved devices and
were thus able to avoid conducting clinical trials to re-prove their safety and
efficacy.
The problem with that, some researchers
claim, is that many
of the original devices which metal-on-metal hips claimed to be ancestors of
have since been recalled from the market under dubious circumstances, meaning
the devices might never have been safe to begin with. Further, the
metal-on-metal hips were not so similar to the original device as to be clearly
substantially equivalent. Devices of this sort are routinely approved and are
referred to as "split predicates."
In light of those concerns—and a lack of action on the part of
Congress during the 2012 passage of the Food and Drug Administration
Safety and Innovation Act to explicitly close the so-called loophole—FDA
announced on 17 January 2013 that it would move to require all metal-on-metal
implant devices to be submitted in the form of a PMA or PDP, which typically
require clinical trials in support of the application and thus an
investigational device exemption (IDE) application as well.
A New Study
But even with these new
requirements, FDA said it is still concerned about hip implants in general, and
most especially with respect to how they are worn down. In the case of metal-on-metal
hips, the chromium coatings of the device wore each other down, in some cases
dislodging metal chromium shavings that caused tissue damage and raised fears
about metal ions entering the bloodstream and causing cancer.
In a solicitation notice posted on
the Federal Business Opportunities (FBO) website, FDA noted that "there is
renewed concern of wear and corrosion of conical head/stem taper junctions in
modern modular total hip replacements." While not a "new
phenomenon," FDA said new design changes like metal-on-metal bearings,
larger femoral heads and modular designs have reintroduced the issue even as
the new features more closely approximate patient features.
As a result, FDA said it's embarking
on a new project to "investigate the potential link between volumetric
wear and corrosion of conical head/stem taper junctions in explanted total hip
replacements and clinical outcomes."
As with nearly all solicitation
notices, it's looking to
the private sector to help it design and run the study, the results of
which will be used to "aid development of standard test methodologies for
preclinical evaluation of total hip implants."
The study will reportedly look at 250 explanted metal-on-metal hip
replacements of various sizes and genders and use the American Society
for Testing and Materials (ASTM) protocol for corrosion testing to analyze
them. "De-identified patient data and radiographs must be available or
obtainable for all devices," the notice explains.
The end goal of the project, which
should take about two years total to conduct, is to generate a peer-reviewed journal article
explaining correlations between wear and corrosion and relevant parameters
(e.g. implantation time, lateral offset, head size, materials, and modularity).
Solicitations are due to FDA by 1 August
2013.
REGULATORY FOCUS Departments: Under RAPS
Quality &
Compliance Science &
Technology Perspective
It's the Law
NEWS
Monday, February 11, 2013
Knowingly implant a failed medical device for profit.
New York Times EDITORIAL
Published: February 10, 2013 FiDA Highlight
All-metal
hip replacements have failed at a high rate and harmed many patients in recent
years. Now there is evidence that a major manufacturer was aware of a serious
problem with one of its models yet failed to alert patients or doctors and
continued to market it aggressively.
The all-metal hips, in which a ball and a cup
component are both made of metal, were thought to be superior in some respects
to traditional hip replacements made of plastic and metal. Some 500,000 people in this
country received all-metal devices over the past decade. They were not adequately tested
because of regulatory loopholes the Food and Drug
Administration is now moving to close, and began
failing not long after implantation.
Thousands of patients have had to replace them in
painful operations; hundreds more have suffered internal damage. Court
documents now show that a major manufacturer, the DePuy Orthopaedics division
of Johnson & Johnson,
buried the bad news about a model known as the Articular Surface Replacement,
the most failure-prone of the implants. The implants were recalled in 2010, but
the documents show that as early as 2008 DePuy
executives were told by a number of surgeons, including its own consultants,
that the device appeared flawed. That was never disclosed to doctors
who were putting the device into patients, nor were other unfavorable internal
studies. By the time of the recall, the device had been implanted in about
93,000 patients around the world.
Surgeons have largely stopped using the
device; even so, the
company is facing more than 10,000 lawsuits in this country related to
past implantations. Though the company says the evidence will ultimately show
that it acted appropriately, it clearly has a lot of explaining t
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