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Prevalence of abnormalities in knees detected by MRI in adults without knee osteoarthritis: population based observational study (Framingham Osteoarthritis Study)

BMJ 2012; 345 doi: (Published 29 August 2012) Cite this as: BMJ 2012;345:e5339
  1. Ali Guermazi, professor of radiology1,
  2. Jingbo Niu, research assistant professor of medicine2,
  3. Daichi Hayashi, research assistant professor of radiology1,
  4. Frank W Roemer, associate professor of radiology13,
  5. Martin Englund, associate professor, epidemiologist24,
  6. Tuhina Neogi, associate professor of medicine and epidemiology2,
  7. Piran Aliabadi, professor of radiology5,
  8. Christine E McLennan, project manager6,
  9. David T Felson, professor of medicine and epidemiology2
  1. 1Department of Radiology, Boston University School of Medicine, FGH Building, 820 Harrison Avenue, Boston, MA 02118, USA
  2. 2Clinical Epidemiology Research and Training Unit, Boston University School of Medicine, Boston
  3. 3Klinikum Augsburg, Department of Radiology, Augsburg, Germany
  4. 4Lund University, Clinical Sciences Lund, Department of Orthopaedics, Lund, Sweden
  5. 5Brigham and Women’s Hospital, Harvard Medical School, Department of Radiology, Boston, MA 02115
  6. 6OptumInsight Life Sciences, Waltham, MA 02451
  1. Correspondence to: A Guermazi guermazi{at}
  • Accepted 23 July 2012


Objective To examine use of magnetic resonance imaging (MRI) of knees with no radiographic evidence of osteoarthritis to determine the prevalence of structural lesions associated with osteoarthritis and their relation to age, sex, and obesity.

Design Population based observational study.

Setting Community cohort in Framingham, MA, United States (Framingham osteoarthritis study).

Participants 710 people aged >50 who had no radiographic evidence of knee osteoarthritis (Kellgren-Lawrence grade 0) and who underwent MRI of the knee.

Main outcome measures Prevalence of MRI findings that are suggestive of knee osteoarthritis (osteophytes, cartilage damage, bone marrow lesions, subchondral cysts, meniscal lesions, synovitis, attrition, and ligamentous lesions) in all participants and after stratification by age, sex, body mass index (BMI), and the presence or absence of knee pain. Pain was assessed by three different questions and also by WOMAC questionnaire.

Results Of the 710 participants, 393 (55%) were women, 660 (93%) were white, and 206 (29%) had knee pain in the past month. The mean age was 62.3 years and mean BMI was 27.9. Prevalence of “any abnormality” was 89% (631/710) overall. Osteophytes were the most common abnormality among all participants (74%, 524/710), followed by cartilage damage (69%, 492/710) and bone marrow lesions (52%, 371/710). The higher the age, the higher the prevalence of all types of abnormalities detectable by MRI. There were no significant differences in the prevalence of any of the features between BMI groups. The prevalence of at least one type of pathology (“any abnormality”) was high in both painful (90-97%, depending on pain definition) and painless (86-88%) knees.

Conclusions MRI shows lesions in the tibiofemoral joint in most middle aged and elderly people in whom knee radiographs do not show any features of osteoarthritis, regardless of pain.


  • Contributors: AG, JN, DH, and DTF conceived and designed the study. AG, JN, FWR, PA, CEM, and DTF collected the data. AG, DH, FWR, ME, TN, and DTF reviewed the literature. AG, JN, DH, FWR, ME, TN, and DTF directed the analyses, which were carried out by JN. All authors participated in the discussion and interpretation of the results. AG and DH organised the writing and wrote the initial drafts. All authors critically revised the manuscript for intellectual content and approved the final versions. AG and DTF are guarantors.

  • Funding: This study was funded by the National Institutes of Health (AG18393 and AR47785) and the Arthritis Foundation. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. The researchers work independently of their funders.

  • Competing interests: All authors have completed the ICMJE uniform disclosure form at (available on request from the corresponding author) and declare: AG is the president of Boston Imaging Core Lab (BICL), LLC, and a consultant to Merck Serono, Stryker, Genzyme, AstraZeneca, and Novartis; FWR a vice president and shareholder of BICL and is a consultant to Merck Serono and National Institute of Health; ME is funded by the Swedish Research Council, the Greta and Johan Kock Foundation, King Gustaf V 80-year Birthday Foundation, and the Faculty of Medicine, Lund University, Sweden; TN is supported by NIAMS AR055127 and the Arthritis Foundation Arthritis Investigator Award.

  • Ethical approval: This study was approved by the institutional review board of Boston University Medical Centre (protocol number H-22674), and written informed consent was obtained from all participants.

  • Data sharing: No additional data available.

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