Alloys used for manufacture of total hip
prostheses contain materials which are potentially carcinogenic in animals.
It is also known that levels of some metals
(Chromium, Nickel, e.g) are elevated both in the tissues around the total hip joint
and in the blood of patients with total hips.
Also bone cement contains materials with potential
carcinogenic effect that may enter into the circulation.
As more and more young patients are operated
on with total hips, the effect of these materials on the bodies of young patients will
last 30 and more years. The question whether total joints may give rise to cancer in the
bodies of their bearers is thus studied intensively.
Questions:
Is there risk that I may develop cancer in the skeleton and
soft tissues around my total joint?
No. Studies demonstrated that cancer in the vicinity of a
total hip or knee joint is extremely rare. During the whole modern history of total joint
replacement only 24 such cases were described among the many millions of patients operated
on worldwide. (Tharani 2001)
Are other forms of cancer, such as stomach, bowel, and
other forms more frequent in patients operated on with total hip and total knee joints?
No. Studies demonstrated that patients with
total hip and knee prostheses implanted in their bodies are not at greater risk to develop
cancer than the people in the general population.
Do patients with more than one total joint prosthesis in
the body, such as patients with bilateral total hip or bilateral total knee replacements
develop more often cancer than people in the general population?
No. The available studies demonstrate that the risk to have
cancer is not greater in patients who have both hips or both knees replaced.
Do patients who have had repeated operations (revision
operations) of their total hip or knee prostheses have cancer more often than the general
population?
No. Available studies demonstrate that cancer risk is not
higher in patients with repeatedly operated total hip or knee prostheses. (Tharani
2001)
Is the risk for having cancer after total knee
replacement different for patients with different diagnoses?
Yes, studies demonstrated that patients with rheumatoid
arthritis have higher risk to develop cancer after total knee replacement than patients
operated for osteoarthritis in their knees.
Is the risk of having cancer after total knee replacement
higher for patients who have had the total knee prosthesis in the body several years?
This question is difficult to answer. One study that
followed patients with total knee replacement for ten years did not find higher
incidence of cancer among them. Studies with longer follow up > 10 years are as
yet lacking for patients with total knee replacements. (Pavolainen 1999)