Patients who
have received a Stryker Rejuvenate hip implant system may be unaware of the
July 2012 recall, or may believe that since the Rejuvenate differs in design
from the metal-on-metal hip implants we’ve heard so much about that they are
relatively safe from harm. Even if those patients are experiencing significant
levels of pain, they may believe that pain stems from the aging process or
other physical ailments rather than from the Rejuvenate.
After all, the
Rejuvenate incorporates a ceramic ball rather than a metal ball, so the belief
is there is little danger of cobalt and chromium ions being released into the
body. This can be a dangerous belief. Stryker stated
that they were recalling the Rejuvenate because of the potential for the neck
juncture to suffer fretting or corrosion, leading in turn to shearing of metal
ions which could lodge in surrounding hip tissues. In addition to the potential
corrosion problem at the neck juncture, the Rejuvenate incorporates metal
“trundles” one either end of the neck portion which allows the neck to snap
into the stem on one end and the ball on the other. When body fluids accumulate
under these trundles, corrosion can occur. Although the surface area is
certainly much less than the all-metal hip implants, meaning fewer metal ions
will shear away into the tissues or bloodstream, even these smaller levels of
cobalt and chromium can lead to significant levels of pain and other health
issues.
Doctors who
are unaware of the different design of the Rejuvenate may dismiss their
patient’s complaints of pain, or, in some cases, may open the patient up, see
no corrosion at the ball and acetabular cup and either replace one of the ball
or cup components or sew the patient back up and send them home. Even at this
point, many doctors are unaware of the potential of corrosion at the trundle
locations which can lead to pain, inflammation and necrosis. The Rejuvenate
patient who suffers chronic pain will likely have little recourse other than to
have the Rejuvenate implant removed during a revision surgery.
Unfortunately,
revision surgery for the Rejuvenate is considerably more risky than revision
surgery for the metal-on-metal implants. Unlike the DePuy Pinnacle revision
surgery which is relatively minor and requires replacement of the liner or the
ASR revision surgery which is more complex, but only requires replacement of
the acetabular cup, the Rejuvenate is completely different. Because the metal
trundles are located between the neck and the stem and the neck and the ball, the
entire Rejuvenate hip implant must be removed. During the original hip
replacement the surgeon would have implanted the stem of the Rejuvenate deep
into the femur, and during revision this stem will have to be dug away from the
bone which has grown around it. Some of these procedures result in shattered
femur bones and a lifetime of problems and pain.
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