Pseudotumors are typically
large, solid or semi-liquid masses which can form around an artificial hip
implant device and can mimic the effects of infection. While pseudotumors are
neither infective nor cancerous, they may be reacting to the metals in a hip
implant or simply to the presence of a foreign body—no matter what it is
constructed of. It appears from research done on hip implant devices that
pseudotumors are more likely to form around implants which are either all-metal
or have metal parts although they may also form around ceramic and polyethylene
implants. When hip implant problems become apparent, a pseudotumor may have
been present for a significant length of time.
The Stryker Rejuvenate and ABG
II both implement a metal neck juncture in the design and have metal trunnions located on either end of the stem piece. Body fluids can
become trapped under the trundles or at the neck juncture, leading to corrosion
and fretting. When the hip implant devices suffer corrosion, premature wear can
result. In turn, this premature wear releases metal debris into the surrounding
hip tissues and bloodstream. Chromium and cobalt toxicity are often found among
patients with metal hip implants or those with metal parts such as the
Rejuvenate and ABG II. The Stryker hip replacement recall for the Rejuvenate
and ABG II was issued in July, 2012, resulting in lawsuits against the company.
It is advisable for anyone considering implantation of a metal hip device to be
tested for metal sensitivities prior to the surgery. Metal poisoning can lead
to a wide variety of serious health symptoms including:
·
Cardiovascular, renal, thyroid and
gastrointestinal disorders
·
Diminished hearing or vision
·
Anxiety, depression or irritability
·
Vertigo or other balance issues
·
Memory loss
·
Disruption of DNA
·
Skin problems
·
Neurological issues
Women appear to have a higher
risk of developing pseudotumors as do those with a higher-than- normal
sensitivity to metals. Considering that among the general population the
prevalence of skin reactions to jewelry containing nickel is relatively high—10
percent—it can be expected that a significant number of adults receiving
implants will be particularly sensitive to the cobalt and chromium. The smaller
component sizes of hip implants required in women are known to be associated
with increased wear and are less forgiving to any level of malposition. Women
who suffer from premature arthritis may also present during hip surgery with
acetabular dysplasia or an abnormal socket inclination.
In many cases pseudotumors
will cause neither pain nor abnormal hip mobility and can go unrecognized for
months or even years. Once a pseudotumor is discovered, it is likely to have
caused significant tissue damage and will require surgery to remove. The most
common symptoms from pseudotumors are chronic pain, diminished range of motion,
inflammation in the hip joint and difficulty walking or engaging in normal
everyday activities. In some cases a pseudotumor can cause a localized rash and
a lump may be apparent. A pseudotumor may be explained as the body’s reaction
to a foreign body—in this case the metal, ceramic or polyethylene hip
implant. In one study of hip implant
devices metal particles were found in every case of pseudotumor development.
Although malposition of the implant was suggested, many properly positioned
implants showed evidence of pseudotumor development. Blood poisoning from metal
toxicity can greatly increase the severity of the pseudotumors, and revision
surgery is almost a given in the presence of pseudotumors. Any recipient of an
artificial hip, particularly those which are all-metal or have metal
components, should undergo x-rays, MRIs and blood testing to determine whether
cobalt and chromium toxicity or pseudotumors are present.
