HOUSTON A knee arthroscopy/placebo study recently
published in the New England Journal of Medicine and widely
reported in the mass media is facing tough criticism by several orthopedic
The research results were not news to any of the knee surgeons
who spoke with ORTHOPEDICS TODAY. The inclusion criteria, however,
were flawed, they said. Perhaps more damaging was the way that the media
covered the article, essentially leading readers to incorrectly conclude that
all knee arthroscopy is ineffective.
Conducted by investigators at Baylor College of Medicine and the
Department of Veterans Affairs, the trial randomized patients with painful
osteoarthritis (OA) to arthroscopic debridement, arthroscopic lavage or a sham
procedure. Patients in all three groups had only moderate improvements in pain
and function at two-year follow-up.
J. Bruce Moseley, MD, who performed all the procedures in the
trial, and colleague Nelda P. Wray, MD, MPH, told ORTHOPEDICS
TODAY that they stand by the results of their study and that many
criticisms are based on limited information available in the NEJM
article. Additional articles providing more details and subgroup analysis have
been submitted for publication or are in preparation, they said.
We feel strongly that the results and conclusions of our
study are accurate and true, and that there is a significant placebo effect
from arthroscopy for OA of the knee.
We feel that arthroscopy for OA of
the knee is beneficial only for a placebo effect, and there are no
Selecting the right
Thomas P. Schmalzried, MD, questioned the patient selection
criteria. The candidate for arthroscopy is not a patient who meets pain
and radiographic criteria. Its a patient who has OA and then has some
internal derangement superimposed on the degenerative joint disease. Nobody
does arthroscopy just for pain. Schmalzried is Joint Reconstruction
section editor for ORTHOPEDICS TODAY.
Moseley and Wray said that trial participants were representative
of typical patients who would be considered for arthroscopy for knee OA after
undergoing nonsurgical treatments. Many patients complained of one or more
mechanical symptoms or effusion, had pain significant enough to seek treatment,
and had exhausted nonsurgical treatments.
Freddie Fu, MD, of the University of Pittsburgh Medical School,
said that for endstage arthritis, arthroscopy is less effective yet it remains
an essential part of the treatment plan for patients with knee OA. There
are many stages of arthritis before patients require a total knee replacement.
That is when arthroscopy is called for, such as staging, diagnosis, to treat a
torn meniscus, loose bodies and for microfracture. I probably agree that if you
have true arthritis
maybe scoping is not that meaningful, Fu
J. Whit Ewing, MD, executive vice president of the Arthroscopy
Association of North America (AANA), said that the patient selection was
flawed. Elements critical to diagnosing and treating patients with knee
OA were omitted or overlooked, such as PA weight-bearing flexion radiographs
and consideration of alignment.
AP standing, flexion weight-bearing PA (the Rosenberg
View), standing hip-ankle AP, lateral and sunrise radiographs were done
to determine a numeric OA grade in the medial, lateral and patellofemoral areas
of the knee, Moseley and Wray said.
The three grades were totaled for an overall arthritis severity
score indicating mild, moderate or severe OA. We had roughly equal
representation for all three groups in our study and the statement that we had
only very bad arthritic knee(s) is not true, they said.
William A. Grana, MD, said: I would ask the authors how
they validated the criteria that they used to determine success and failure. To
do an outcome study like this you have to validate the instruments youre
using. Grana is secretary of AANA and is the Sports Medicine section
editor for ORTHOPEDICS TODAY.
The researchers said that most of our measurement
instrument was taken from instruments with proven reliability and
validity, such as the SF-36 general health measure, the AIMS-2 pain scale and
Wisconsin brief pain questionnaire.
We also developed some questions
this study, which were extensively analyzed and found to have high
reliability and validity.
Media coverage disturbing
Media reports of the trial are being criticized. The
article and particularly the Associated Press report disturbs me
very much, said ORTHOPEDICS TODAY Chief Medical Editor John
B. McGinty, MD.
Moseley and Wray said they also have concerns about how the media
handled the story. We are in agreement that the media has, in many
instances, condemned all arthroscopic surgery on the basis of our study. This
has occurred in spite of our efforts to the contrary.
Kenneth E. DeHaven, MD, of Rochester, N.Y., said his
biggest concern about this study is that it may not be kept in
perspective, and that it is automatically extrapolated to all types of
Moseley and Wray said that the media have failed to report that
arthroscopic surgery is appropriate in unarthritic knees for several
indications. We have emphasized this consistently in our dealings with
the media, but this is one of the unexciting details that seems to get edited
out of most stories.
The negative press has not helped the longtime public relations
campaign that members of AANA have been informally conducting concerning knee
arthroscopy. This is a damaging paper in terms of patient
confidence, Ewing said.
He said that members of AANA have tried to educate surgeons that
knee arthroscopy is not indicated for patients with arthritic knee pain and
swelling alone, and that it should be reserved for those presenting with pain
in conjunction with mechanical knee problems, like locking or catching.
In mid-July, Ewing was preparing AANAs response to the
NEJM study, which the organization planned to publish in a major
newspaper or medical journal. The document stated: The article
leads the casual reader to think that arthroscopic surgery is useless for any
type of knee surgery involving arthritis. This is most unfortunate.
AANA called for evaluation of patients at a longer follow-up than
two years. There is too much chance that the placebo effect will still be
in effect if the result is determined in less than two years of
follow-up. In response, Moseley and Wray said that two years is the
standard for publication in most orthopedic journals and this was a more
than adequate amount of time to evaluate the effectiveness of an arthroscopy
The AAOS perspective
The AAOS issued a response, praising the studys use of
evidence-based medicine, a large number of patients, an excellent control group
and long-term assessment.
The weaknesses include a potential selection bias caused by
the number of patients who decided not to participate and the nonspecific
indications for arthroscopy, AAOS executive vice president William W.
Tipton Jr., MD, reported. Of the 324 patients who met the inclusion criteria,
144 declined to participate.
While the AAOS found the study ethically sound, the organization
said the results should be reproduced in a non-VA setting with selection for
pre-existing malalignment, mechanical symptoms, body weight and other factors.
We would also agree with the authors that an expert panel
be convened to review the findings of this study and make recommendations as to
the selective use of arthroscopy in the treatment of OA of the knee.
Ethics of placebo
This method, a randomized controlled study with a control
treatment, a placebo method, is the gold standard for all clinical studies, but
it is not always ethical. Some people would question whether this was ethical
or not, Grana said.
Two complications were reported in the 165 patients who completed
the trial. One patient developed incisional erythema, which was treated with
antibiotics. Another had calf swelling in the operated leg. In no case
did a complication necessitate the breaking of the randomization code,
Even though an editorial in the NEJM said the trial
exemplifies the ethically justified use of placebo surgery,
Schmalzried disagreed. I dont like the idea of having a placebo
procedure, he said.
The heart of the ethical issues surrounding this study lies in
those patients who were treated. The real editorial should have been on
the ethics of operating on people that shouldnt have been operated on at
all, Schmalzried said.
We feel very strongly about the ethics of our study,
Moseley and Wray said. We had a nationally recognized ethicist involved
in the study from its onset. Once it was determined that placebo
arthroscopy could be safely performed, [Baruch A. Brody, PhD] felt it
would be unethical to not perform the study.
For your information:
- Moseley JB, OMalley K, Petersen NJ, et al. A
controlled trial of arthroscopic surgery for osteoarthritis of the knee.
N Engl J Med. 2002;347:81-88.
- Horng S, Miller FG. Is placebo surgery unethical? N
Engl J Med. 2002;347:137-139.