Ann Rheum Dis 64:1703-1709 doi:10.1136/ard.2005.037994
  • Extended report

EULAR report on the use of ultrasonography in painful knee osteoarthritis. Part 1: Prevalence of inflammation in osteoarthritis

  1. M A D’Agostino1,*,
  2. P Conaghan2,
  3. M Le Bars3,
  4. G Baron4,
  5. W Grassi5,
  6. E Martin-Mola6,
  7. R Wakefield2,
  8. J-L Brasseur7,
  9. A So8,
  10. M Backhaus9,
  11. M Malaise10,
  12. G Burmester9,
  13. N Schmidely3,
  14. P Ravaud4,
  15. M Dougados1,
  16. P Emery2
  1. 1Rheumatology Department, Cochin Hospital, Paris, France
  2. 2University of Leeds and Rheumatology Department, Leeds General Infirmary, Leeds, UK
  3. 3Bristol Myers-Squibb, Reuil-Malmaison, France
  4. 4Epidemiology, Biostatistics and Clinical Research Department, Bichat Hospital, Paris, France
  5. 5Rheumatology Department, Jesi Hospital, Jesi, Italy
  6. 6Rheumatology Department, La Paz Hospital, Madrid, Spain
  7. 7Radiology Department, Pitié Salpêtrière Hospital, Paris, France
  8. 8Rheumatology Department, Vaudois Hospital, Lausanne, Switzerland
  9. 9Rheumatology Department, Charité University Hospital, Berlin, Germany
  10. 10Rheumatology Department, Saint Tiltman Hospital, Liege, Belgium
  1. Correspondence to:
    Professor M Dougados
    Rheumatology Department, Cochin Hospital, 27, rue du Faubourg St Jacques, 75014 Paris, France;
  • Accepted 23 April 2005
  • Published Online First 5 May 2005


Objectives: To assess the prevalence of inflammation in subjects with chronic painful knee osteoarthritis (OA), as determined by the presence of synovitis or joint effusion at ultrasonography (US); and to evaluate the correlation between synovitis, effusion, and clinical parameters.

Methods: A cross sectional, multicentre, European study was conducted under the umbrella of EULAR-ESCISIT. Subjects had primary chronic knee OA (ACR criteria) with pain during physical activity ⩾30 mm for at least 48 hours. Clinical parameters were collected by a rheumatologist and an US examination of the painful knee was performed by a radiologist or rheumatologist within 72 hours of the clinical examination. Ultrasonographic synovitis was defined as synovial thickness ⩾4 mm and diffuse or nodular appearance, and a joint effusion was defined as effusion depth ⩾4 mm.

Results: 600 patients with painful knee OA were analysed. At US 16 (2.7%) had synovitis alone, 85 (14.2%) had both synovitis and effusion, 177 (29.5%) had joint effusion alone, and 322 (53.7%) had no inflammation according to the definitions employed. Multivariate analysis showed that inflammation seen by US correlated statistically with advanced radiographic disease (Kellgren-Lawrence grade ⩾3; odds ratio (OR) = 2.20 and 1.91 for synovitis and joint effusion, respectively), and with clinical signs and symptoms suggestive of an inflammatory “flare”, such as joint effusion on clinical examination (OR = 1.97 and 2.70 for synovitis and joint effusion, respectively) or sudden aggravation of knee pain (OR = 1.77 for joint effusion).

Conclusion: US can detect synovial inflammation and effusion in painful knee OA, which correlate significantly with knee synovitis, effusion, and clinical parameters suggestive of an inflammatory “flare”.


  • * Current address: Rheumatology Department, Ambroise Paré Hospital, Boulogne-Billancourt, France.

  • Published Online First 5 May 2005