Surgeons have learned over the
past decade that newer versions of hip implants, made with a metal ball that
fits into a metal socket, such as the DePuy Pinnacle, have been failing at a
higher rate than traditional hip implants made of ceramic or plastic parts,
medical industry publications report. Typically, most hip implants fracture,
loosen, or dislocate over a decade or two due to wear and tear. But many of
these metal implants, designed to be more durable than traditional implants,
are failing after five years or less.
While there are several problems
associated with these artificial hip implants, the most painful one among the
side effects involves a loosening of the hip implant, something that has been
repeatedly documented through consumer complaints and FDA reports. Loosening of
the hip replacement can actually happen over time, and usually causes problems
with the normal function of the hip replacement. When a hip replacement is
placed into the body, it is either press-fit into the bone, or cemented into
position. Either way, it is fit tightly into the bone of the thigh (femur) and
pelvis so that the implant cannot move. When the implant begins to loosen, the
hip replacement will also begin to move in small amounts. If this happens the
patient usually begin to feel pain.
The unfortunate part for the
patients whose hip replacement has become loose, is that hip replacement
revision surgery is one of the only ways to correct the loosening.The biggest
problem with this is that, after revision operations, patients tend to recover
less overall motion of the joint. The implant durability also declines with
each revision. It is because of this
that surgeons avoid revision surgery unless it is absolutely necessary as to
get the most of the implant already in the patient.
With increasing amount of
complaints about metal-on-metal hip implants loosening prematurely, the United
States food and Drug Administration (FDA) has, in 2010, ordered 21
manufacturers to conduct studies on patients who have received the implants.
Included in the 21 manufacturers is DePuy and its DePuy Pinnacle hip
replacement system. The FDA will then determine its course of action on
metal-on-metal hip replacements according to the results of this test.