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Information from Dr. De Smet's Website
Link
to Dr. De Smets Website and Original Article
http://www.hip-clinic.com:80/en/html/metal_allergy.html
(from www.metalsensitivity.com)
Occasional reports of joint replacement implant failure because of an apparent
allergy to
one of the metals in the device have appeared in the orthopedic literature ever
since metal
implants were used. (1-3) It is now recognized that a small number of patients
will suffer
from a form of allergy or hypersensitivity to constituents of the metal-on-metal
bearings even
in the absence of high wear or a known metal sensitivity (4-6). The histological
features of the
reaction characterizing the joint tissues from these hypersensitive patients are
different from
the classical text-book form of Type 4 DTH. (7) For this reason, the term ALVAL
(aseptic
lymphocytic vasculitis associated lesions) has been coined to describe the
histological features
associated with an allergy-like reaction in the joint tissues. (8) It should be
noted that some
pathologists object to the inclusion of the “vasculitis” part of this new name
and vasculitis in
the strict sense of the word is not a prominent feature of the lesions.
The characteristic histological features in the periprosthetic tissues are
infiltrates of
lymphocytes, often with plasma cells, arranged perivascularly or in dense
aggregates. In
severe cases, there may be a wide necrotic tidemark between the tissue edge and
the
lymphocytes which are then arranged in a broad band at the back of the tissue
section. These
infiltrates appear in the absence of infection or mechanical causes for pain. It
is important to
note that lymphocytes can be present in relatively large numbers in response to
excessive
wear debris and the reason for their presence is unclear (9,10).
Diagnosing metal sensitivity can be difficult, and it may be hard to
differentiate it from a
reaction to excessive wear or to infection if an organism is not cultured from
the tissue or joint
fluid. There is a wide variety of clinical presentations of metal sensitivity;
typically the
patients report ongoing pain or discomfort, typically in the groin, often
accompanied over
time with an effusion which may progress to form an enlarged fluid hernia or a
groin mass. If
all possible causes for the patient’s pain can be eliminated by imaging or
hematological
testing, a diagnosis of metal sensitivity should be entertained and if
confirmed, the cobalt
chromium bearings should be removed to avoid ongoing soft tissue damage. (11)
The number
of revisions performed to remove cobalt chromium bearings because of a metal
allergy is
unknown, but it is thought to be a relatively rare complication.
Skin Sensitivity and Hip Sensitivity
Approximately 10–15% of the general population has a
skin sensitivity to metal, nickel being the most common
sensitizer, followed by cobalt and chromium. (5) There is
concern, therefore, that patients with a skin sensitivity will also
have an adverse reaction to a cobalt chromium hip replacement
although there is little actual evidence to support this concern. It
should be noted that the FDA lists skin sensitivity as a contraindication to
metal-on-metal hip
resurfacing.
A small retrospective survey of patients with a metal-on-metal hip resurfacing
arthroplasties was carried out at one center which performs a large number of
hip
resurfacings (the Joint Replacement Institute, St Vincent’s Hospital, Los
Angeles ). Patients
were asked about reactivity to jewelry (type of jewelry involved, the metal
involved, and the
nature of the reaction). One hundred seventy-eight patients responded (142 male
35 female)
and 21 (5.6%) reported they had a skin problem, mostly to stainless steel (which
contains a
small amount of nickel) or “cheap” jewelry in the form of rashes, redness and
itching. Of
those 21, 11 were male and 13 were female, but since most of the overall patient
cohort was
male, the proportion of females with skin reactions was relatively higher.
However,
regardless of their problems with jewelry, none of these patients had any
problems with their
hip replacement. Unfortunately, patch tests that can demonstrate skin
sensitivity are not
reliable to predict if a problem will occur in the hip after a cobalt chromium
implant is
inserted. Newer blood tests as “lymphocyte aggregation” tests are also not yet
reliable, but
research into better screening tests for metal sensitivity is ongoing.
In my Orthopaedic Practice
The definitive diagnose of metalsensitivity only can be given after examination
by an
experienced anatomopathologist of thetissues surrounding the prosthesis. On
x-rays these soft
tissue and bonychanges can be seen as progressive necknarrowing (white arrows),
osteolytic
lines (bone that is absent) around the stem of the resurfacing head (yellow
arrows) and
osteolysis even behind the cup (black arrows).
Taking in account that most of the metal sensitivity cases are seen after a time
frame of
more then 3 years, the incidence in my patient series is 6/1346.( Number
ofpatients with
longer follow up then 3 years (3-9y))
This incidence ofapproximate 1/200 should even be equated to be higher in
females
(1/60) because the only allergies are seen in females, who are only 1/3 of the
whole
resurfacing group. Timely revision should be performed to avoid progressive
local tissue
damage.
With special thanks to Pat Campbell PhD Orthopaedic Hospital/UCLA, Los
Angeles, CA USA
Pat Campbell, Ph.D. Director, Implant Retrieval Lab.
J. Vernon Luck, Sr., MD Orthopaedic Research Center ,
UCLA/ Orthopedic Hospital
Scott D. Nelson MD, Chief of Pathology
Santa Monica UCLA/ Orthopedic Hospital
References
1. Evans EM, Freeman MAR, Miller AJ, and Vernon-Roberts B: Metal sensitivity as
a cause
of bone necrosis and loosening of the prosthesis in total joint replacement. J
Bone Joint Surg
56B:626-642, 1974.
2. Vernon-Roberts B, and Freeman MAR: Morphological and Analytical Studies of
the
Tissues Adjacent to Joint Prostheses: Investigations Into the Causes of
Loosening of
Prostheses. IN Schaldach M Hofmann D (eds). Advances in Hip and Knee Joint
Technology,
Springer-Verlag, New York, 1976, 148-186.
3. Deutman R, Mulder THJ, Brian R, and Nater JP: Metal sensitivity before and
after total
hip arthroplasty. J Bone Joint Surg 59A:862-865, 1977.
4. Gawkrodger DJ: Metal sensitivities and orthopaedic implants revisited: the
potential for
metal allergy with the new metal-on-metal joint prostheses. Br J Dermatol.
148:1089-1093.,
2003.
5. Hallab N, Merritt K, and Jacobs JJ: Metal sensitivity in patients with
orthopaedic implants.
J Bone Joint Surg 83A:428-436., 2001.
6. Willert H, Buchorn G, Fayaayazi A, and Lohmann C: Histopathological changes
around
metal/metal joints indicate delayed type hypersensitivity. Preliminary results
of 14 cases.
Osteologie 9:2-16, 2000.
7. Davies AP, Willert HG, Campbell PA, Learmonth ID, and Case CP: An Unusual
Lymphocytic Perivascular Infiltration in Tissues Around Contemporary
Metal-on-Metal Joint
Replacements. J Bone Joint Surg 87:18-27, 2005.
8. Willert H-G, Buchhorn GH, Dipl-Ing, Fayyazi A, Flury R, Windler M, Koster G,
and
Lohmann CH: Metal-on-metal bearings and hypersensitivity in patients with
artificial hip
joints. A clinical and histomorphological study. J Bone Joint Surg 87:28-36,
2005.
9. Campbell P, Mirra J, Doorn P, Mills B, Alim R, and Catelas I: Histopathology
of Metal-
on-Metal Hip Joint Tissues. IN Rieker C, Oberholzer S, Wyss U (eds). World
Tribology
Forum in Arthroplasty, Hans Huber, Gottingen, 2000, 167-180.
10. Campbell P, Beaule P, Ebramzadeh E, Le Duff M, De Smet K, Lu Z, and Amstutz
H: A
study of implant failure in metal-on-metal surface arthroplasties. Clin Orthop
453:35-46,
2006.
11. Campbell P, Shimmin A, Walter L, and Solomon M: Metal Sensitivity as a Cause
of
Groin Pain in Metal-on-Metal Hip Resurfacing. J Arthroplasty in press:2007.
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