Osteoarthritis of the knee at 3.0 T: comparison of a quantitative and a semi-quantitative score for the assessment of the extent of cartilage lesion and bone marrow edema pattern in a 24-month longitudinal study

Skeletal Radiol. 2011 Oct;40(10):1315-27. doi: 10.1007/s00256-011-1156-9. Epub 2011 Apr 9.


Objective: To compare a semi-quantitative and a quantitative morphological score for assessment of early osteoarthritis (OA) evolution.

Materials and methods: 3.0 T MRI of the knee was performed in 60 women, 30 with early OA (each 15 with Kellgren-Lawrence grade 2 and 3) and 30 age-matched controls at baseline and at 12 and 24 months. Pathological condition was assessed with the whole-organ magnetic resonance imaging score (WORMS). Cartilage abnormalities and bone marrow edema pattern (BMEP) were also quantified using a previously introduced morphological quantitative score. These data were correlated with changes in clinical parameters and joint space width using generalized estimation equations (GEE).

Results: At baseline, OA patients had significantly (p < 0.05) more and larger cartilage lesions and BMEP. During follow-up, cartilage lesions increased significantly (p < 0.05) in the patients compared with controls: WORMS showed progression only at the lateral patella, whereas the quantitative score revealed progression additionally at the trochlea and at the medial compartment. Both scores showed a significant (p < 0.05) increase in BMEP at the lateral femur in OA patients. In addition, quantitative scores of BMEP of the whole knee decreased significantly (p < 0.05) after 12 months and increased after 24 months in the patients, but showed an increase in controls at all follow-up examinations. Only weak correlations between structural imaging findings and clinical parameters were observed.

Conclusion: Quantitative assessment of cartilage lesions and BMEP is more sensitive to changes during the course of the disease than semi-quantitative scoring. However, structural imaging findings do not correlate well with the clinical progression of OA.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Bone Marrow / pathology*
  • Cartilage, Articular / pathology
  • Disease Progression
  • Edema / pathology
  • Feasibility Studies
  • Female
  • Humans
  • Longitudinal Studies
  • Magnetic Resonance Imaging*
  • Middle Aged
  • Osteoarthritis, Knee / pathology*
  • Reproducibility of Results