Jan 17 Metal-on-metal hip implants can cause
soft-tissue damage and pain, which could lead to further surgery
to replace the implant, the U.S. health regulator said,
following several recalls of the artificial hip parts.
All-metal hip implants were developed to be more durable
than traditional implants but have become a major cause of
concern following several safety issues and user discomforts.
The traditional implants combine a ceramic or metal ball
with a plastic socket.
The U.S. Food and Drug Administration said all-metal
implants can shed metal where two components connect, such as
the ball and the cup that slide against each other during
walking or running. ()
Such release of metal will cause wear and tear of the
implant and can damage bone and soft tissue surrounding the
The agency said surgeons should select a metal-on-metal hip
implant for their patient only after determining that its
benefits outweigh that of an alternative hip system.
Johnson & Johnson, the biggest manufacturer of
all-metal devices, recalled its ASR hip implant in 2010
following safety problems.
Smith & Nephew withdrew a component of one of its
all-metal artificial hip systems last June, following higher
level of patient problems with the device. Stryker Corp
begun recalling some components of its implant in July due to
risks associated with corrosion.
Other hip implant makers include Zimmer Holdings Inc
and Wright Medical Group.
The regulator, however, added that it does not have enough
data to specify the concentration of metal ions in a patient's
body or blood necessary to produce adverse effects.
The reaction seemed to be specific to individual patients,
the FDA said on its website.