Table Of ContentTHE DIAGNOSIS OF PERIPROSTHETIC JOINT
INFECTIONS OF THE HIP AND KNEE
GUIDELINE AND EVIDENCE REPORT
Adopted by the American Academy of Orthopaedic Surgeons
Board of Directors
June 18, 2010
Disclaimer
This Clinical Practice Guideline was developed by an AAOS physician volunteer Work
Group based on a systematic review of the current scientific and clinical information and
accepted approaches to treatment and/or diagnosis. This Clinical Practice Guideline is not
intended to be a fixed protocol, as some patients may require more or less treatment or
different means of diagnosis. Clinical patients may not necessarily be the same as those
found in a clinical trial. Patient care and treatment should always be based on a
clinician’s independent medical judgment, given the individual patient’s clinical
circumstances.
Disclosure Requirement
In accordance with AAOS policy, all individuals whose names appear as authors or
contributors to Clinical Practice Guideline filed a disclosure statement as part of the
submission process. All panel members provided full disclosure of potential conflicts of
interest prior to voting on the recommendations contained within this Clinical Practice
Guidelines.
Funding Source
This Clinical Practice Guideline was funded exclusively by the American Academy of
Orthopaedic Surgeons who received no funding from outside commercial sources to
support the development of this document.
FDA Clearance
Some drugs or medical devices referenced or described in this Clinical Practice Guideline
may not have been cleared by the Food and Drug Administration (FDA) or may have
been cleared for a specific use only. The FDA has stated that it is the responsibility of the
physician to determine the FDA clearance status of each drug or device he or she wishes
to use in clinical practice.
Copyright
All rights reserved. No part of this Clinical Practice Guideline may be reproduced, stored
in a retrieval system, or transmitted, in any form, or by any means, electronic,
mechanical, photocopying, recording, or otherwise, without prior written permission
from the AAOS.
Published 2010 by the American Academy of Orthopaedic Surgeons
6300 North River Road
Rosemont, IL 60018
First Edition
Copyright 2010
by the American Academy of Orthopaedic Surgeons
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Summary of Recommendations
The following is a summary of the recommendations in the AAOS’ clinical practice
guideline, The Diagnosis of Periprosthetic Joint Infections of the Hip and Knee. This
summary does not contain rationales that explain how and why these recommendations
were developed nor does it contain the evidence supporting these recommendations. All
readers of this summary are strongly encouraged to consult the full guideline and
evidence report for this information. We are confident that those who read the full
guideline and evidence report will note that the recommendations were developed using
systematic evidence-based processes designed to combat bias, enhance transparency, and
promote reproducibility.
This summary of recommendations is not intended to stand alone. Clinical decisions
should be made in light of all circumstances presented by the patient. Procedures
applicable to the individual patient rely on mutual communication between patient,
physician, and other healthcare practitioners.
1. In the absence of reliable evidence about risk stratification of patients with a
potential periprosthetic joint infection, it is the opinion of the work group that
testing strategies be planned according to whether there is a higher or lower
probability that a patient has a hip or knee periprosthetic infection.
Strength of Recommendation: Consensus
Description: The supporting evidence is lacking and requires the work group to make a
recommendation based on expert opinion by considering the known potential harm and
benefits associated with the treatment. A Consensus recommendation means that expert
opinion supports the guideline recommendation even though there is no available
empirical evidence that meets the inclusion criteria of the guideline’s systematic review.
Implications: Practitioners should be flexible in deciding whether to follow a
recommendation classified as Consensus, although they may set boundaries on
alternatives. Patient preference should have a substantial influencing role.
Note: Please see page 17 of this document for a definition of “higher and lower
probability”.
2. We recommend erythrocyte sedimentation rate and C-reactive protein testing
for patients assessed for periprosthetic joint infection.
Strength of Recommendation: Strong
Description: Evidence is based on two or more “High” strength studies with consistent
findings for recommending for or against the intervention. A Strong recommendation
means that the benefits of the recommended approach clearly exceed the potential harm
(or that the potential harm clearly exceeds the benefits in the case of a strong negative
recommendation), and that the strength of the supporting evidence is high.
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Implications: Practitioners should follow a Strong recommendation unless a clear and
compelling rationale for an alternative approach is present.
3. We recommend joint aspiration of patients being assessed for periprosthetic
knee infections who have abnormal erythrocyte sedimentation rate AND/OR C-
reactive protein results. We recommend that the aspirated fluid be sent for
microbiologic culture, synovial fluid white blood cell count and differential.
Strength of Recommendation: Strong
Description: Evidence is based on two or more “High” strength studies with consistent
findings for recommending for or against the intervention. A Strong recommendation
means that the benefits of the recommended approach clearly exceed the potential harm
(or that the potential harm clearly exceeds the benefits in the case of a strong negative
recommendation), and that the strength of the supporting evidence is high.
Implications: Practitioners should follow a Strong recommendation unless a clear and
compelling rationale for an alternative approach is present.
4. We recommend a selective approach to aspiration of the hip based on the
patient’s probability of periprosthetic joint infection and the results of the
erythrocyte sedimentation rate (ESR) AND C-reactive protein (CRP). We
recommend that the aspirated fluid be sent for microbiologic culture, synovial
fluid white blood cell count and differential.
Selection of Patients for Hip Aspiration
Probability of ESR and CRP Planned Reoperation
Infection Results Status Recommended Test
Higher + + or + − Planned or not planned Aspiration
Lower + + or + − Planned Aspiration or Frozen Section
Lower + + Not planned Aspiration
Lower + − Not planned Please see Recommendation 6
Higher or Lower − − Planned or not planned No further testing
Key for ESR and CRP results
+ + = ESR and CRP test results are abnormal
+ − = either ESR or CRP test result is abnormal
− − = ESR and CRP test results are normal
Strength of Recommendation: Strong
Description: Evidence is based on two or more “High” strength studies with consistent
findings for recommending for or against the intervention. A Strong recommendation
means that the benefits of the recommended approach clearly exceed the potential harm
(or that the potential harm clearly exceeds the benefits in the case of a strong negative
recommendation), and that the strength of the supporting evidence is high.
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Implications: Practitioners should follow a Strong recommendation unless a clear and
compelling rationale for an alternative approach is present.
5. We suggest a repeat hip aspiration when there is a discrepancy between the
probability of periprosthetic joint infection and the initial aspiration culture
result.
Strength of Recommendation: Moderate
Description: Evidence from two or more “Moderate” strength studies with consistent
findings, or evidence from a single “High” quality study for recommending for or against
the intervention. A Moderate recommendation means that the benefits exceed the
potential harm (or that the potential harm clearly exceeds the benefits in the case of a
negative recommendation), but the strength of the supporting evidence is not as strong.
Implications: Practitioners should generally follow a Moderate recommendation but
remain alert to new information and be sensitive to patient preferences.
6. In the absence of reliable evidence, it is the opinion of the work group that
patients judged to be at lower probability for periprosthetic hip infection and
without planned reoperation who have abnormal erythrocyte sedimentation rates
OR abnormal C-reactive protein levels be re-evaluated within three months. We
are unable to recommend specific diagnostic tests at the time of this follow-up.
Strength of Recommendation: Consensus
Description: The supporting evidence is lacking and requires the work group to make a
recommendation based on expert opinion by considering the known potential harm and
benefits associated with the treatment. A Consensus recommendation means that expert
opinion supports the guideline recommendation even though there is no available
empirical evidence that meets the inclusion criteria of the guideline’s systematic review.
Implications: Practitioners should be flexible in deciding whether to follow a
recommendation classified as Consensus, although they may set boundaries on
alternatives. Patient preference should have a substantial influencing role.
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7. In the absence of reliable evidence, it is the opinion of the work group that a
repeat knee aspiration be performed when there is a discrepancy between the
probability of periprosthetic joint infection and the initial aspiration culture
result.
Strength of Recommendation: Consensus
Description: The supporting evidence is lacking and requires the work group to make a
recommendation based on expert opinion by considering the known potential harm and
benefits associated with the treatment. A Consensus recommendation means that expert
opinion supports the guideline recommendation even though there is no available
empirical evidence that meets the inclusion criteria of the guideline’s systematic review.
Implications: Practitioners should be flexible in deciding whether to follow a
recommendation classified as Consensus, although they may set boundaries on
alternatives. Patient preference should have a substantial influencing role.
8. We suggest patients be off of antibiotics for a minimum of 2 weeks prior to
obtaining intra-articular culture.
Strength of Recommendation: Moderate
Description: Evidence from two or more “Moderate” strength studies with consistent
findings, or evidence from a single “High” quality study for recommending for or against
the intervention. A Moderate recommendation means that the benefits exceed the
potential harm (or that the potential harm clearly exceeds the benefits in the case of a
negative recommendation), but the strength of the supporting evidence is not as strong.
Implications: Practitioners should generally follow a Moderate recommendation but
remain alert to new information and be sensitive to patient preferences.
9. Nuclear imaging (Labeled leukocyte imaging combined with bone or bone
marrow imaging, FDG-PET imaging, Gallium imaging, or labeled leukocyte
imaging) is an option in patients in whom diagnosis of periprosthetic joint
infection has not been established and are not scheduled for reoperation.
Strength of Recommendation: Limited
Description: Evidence from two or more “Low” strength studies with consistent findings,
or evidence from a single “Moderate” quality study recommending for or against the
intervention or diagnostic. A Limited recommendation means the quality of the
supporting evidence that exists is unconvincing, or that well-conducted studies show little
clear advantage to one approach versus another.
Implications: Practitioners should be cautious in deciding whether to follow a
recommendation classified as Limited, and should exercise judgment and be alert to
emerging publications that report evidence. Patient preference should have a substantial
influencing role.
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10. We are unable to recommend for or against computed tomography (CT) or
magnetic resonance imaging (MRI) as a diagnostic test for periprosthetic joint
infection.
Strength of Recommendation: Inconclusive
Description: Evidence from a single low quality study or conflicting findings that do not
allow a recommendation for or against the intervention. An Inconclusive
recommendation means that there is a lack of compelling evidence resulting in an unclear
balance between benefits and potential harm.
Implications: Practitioners should feel little constraint in deciding whether to follow a
recommendation labeled as Inconclusive and should exercise judgment and be alert to
future publications that clarify existing evidence for determining balance of benefits
versus potential harm. Patient preference should have a substantial influencing role.
11. We recommend against the use of intraoperative Gram stain to rule out
periprosthetic joint infection.
Strength of Recommendation: Strong
Description: Evidence is based on two or more “High” strength studies with consistent
findings for recommending for or against the intervention. A Strong recommendation
means that the benefits of the recommended approach clearly exceed the potential harm
(or that the potential harm clearly exceeds the benefits in the case of a strong negative
recommendation), and that the strength of the supporting evidence is high.
Implications: Practitioners should follow a Strong recommendation unless a clear and
compelling rationale for an alternative approach is present.
12. We recommend the use of frozen sections of peri-implant tissues in patients
who are undergoing reoperation for whom the diagnosis of periprosthetic joint
infection has not been established or excluded.
Strength of Recommendation: Strong
Description: Evidence is based on two or more “High” strength studies with consistent
findings for recommending for or against the intervention. A Strong recommendation
means that the benefits of the recommended approach clearly exceed the potential harm
(or that the potential harm clearly exceeds the benefits in the case of a strong negative
recommendation), and that the strength of the supporting evidence is high.
Implications: Practitioners should follow a Strong recommendation unless a clear and
compelling rationale for an alternative approach is present.
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13. We recommend that multiple cultures be obtained at the time of reoperation in
patients being assessed for periprosthetic joint infection.
Strength of Recommendation: Strong
Description: Evidence is based on two or more “High” strength studies with consistent
findings for recommending for or against the intervention. A Strong recommendation
means that the benefits of the recommended approach clearly exceed the potential harm
(or that the potential harm clearly exceeds the benefits in the case of a strong negative
recommendation), and that the strength of the supporting evidence is high.
Implications: Practitioners should follow a Strong recommendation unless a clear and
compelling rationale for an alternative approach is present.
14. We recommend against initiating antibiotic treatment in patients with suspected
periprosthetic joint infection until after cultures from the joint have been
obtained.
Strength of Recommendation: Strong
Description: Evidence is based on two or more “High” strength studies with consistent
findings for recommending for or against the intervention. A Strong recommendation
means that the benefits of the recommended approach clearly exceed the potential harm
(or that the potential harm clearly exceeds the benefits in the case of a strong negative
recommendation), and that the strength of the supporting evidence is high.
Implications: Practitioners should follow a Strong recommendation unless a clear and
compelling rationale for an alternative approach is present.
15. We suggest that prophylactic preoperative antibiotics not be withheld in patients
at lower probability for periprosthetic joint infection and those with an
established diagnosis of periprosthetic joint infection who are undergoing
reoperation.
Strength of Recommendation: Moderate
Description: Evidence from two or more “Moderate” strength studies with consistent
findings, or evidence from a single “High” quality study for recommending for or against
the intervention. A Moderate recommendation means that the benefits exceed the
potential harm (or that the potential harm clearly exceeds the benefits in the case of a
negative recommendation), but the strength of the supporting evidence is not as strong.
Implications: Practitioners should generally follow a Moderate recommendation but
remain alert to new information and be sensitive to patient preferences.
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Work Group
Craig Della Valle MD, Chair Guidelines and Technology Oversight
Rush University Medical Center Chair:
1611 W Harrison St # 300 William C. Watters III MD
Chicago, IL 60612-4861 6624 Fannin #2600
Houston, TX 77030
Javad Parvizi, MD, Vice-Chair
Rothman Institute Evidence Based Practice Committee Chair:
925 Chestnut St - 5th Fl Michael Keith, MD
Philadelphia, PA 19107 2500 Metro Health Drive
Cleveland, OH 44109-1900
Thomas W Bauer, MD PhD
Cleveland Clinic Foundation AAOS Staff:
Department of Pathology Charles M. Turkelson, PhD
9500 Euclid Ave Desk L25 Director of Research and Scientific Affairs
Cleveland, OH 44195 6300 N River Road
Rosemont, IL 60018
Paul E DiCesare, MD
UC Davis Medical Center Janet L. Wies MPH
Department of Orthopaedic Surgery AAOS Clinical Practice Guideline Mgr
4860 Y St Ste 3800
Sacramento, CA 95817 Patrick Sluka MPH
AAOS Research Analyst
Richard Parker Evans, MD
University of Arkansas for Medical Sciences Kristin Hitchcock, MSI
Department of Orthopedics AAOS Medical Librarian
4301 W Markham, #531
Little Rock, AR 72205 Special Acknowledgements
Sara Anderson MPH
John Segreti, MD Kevin Boyer
Rush University Medical Center Laura Raymond, MA
600 S Paulina St. Ste 143
Chicago, Il 60612
Mark Spangehl, MD
Mayo Clinic
5777 East Mayo Blvd
Phoenix, AZ 85054
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Peer Review
Participation in the AAOS peer review process does not constitute an endorsement
of this guideline by the participating organization.
The following organizations participated in peer review of this clinical practice guideline
and gave explicit consent to be listed in this document:
American Association of Hip and Knee Surgeons
European Bone and Joint Infection Society
Knee Society
Musculoskeletal Infection Society
Society of Nuclear Medicine
Participation in the AAOS peer review process does not constitute an endorsement
of this guideline by the participating organization.
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Description:Group based on a systematic review of the current scientific and clinical
information and accepted found in a clinical trial. Patient care and treatment
should always be based on a clinical practice guideline, The Diagnosis of
Periprosthetic Joint Infections of the Hip and Knee. Rush University
