Assessment of subchondral bone marrow lesions in knee osteoarthritis by MRI: a comparison of fluid sensitive and contrast enhanced sequences

Abstract

BackgroundBone marrow lesions (BMLs) in knee osteoarthritis (OA) can be assessed using fluid sensitive and contrast enhanced sequences. The association between BMLs and symptoms has been investigated in several studies but only using fluid sensitive sequences. Our aims were to assess BMLs by contrast enhanced MRI sequences in comparison with a fluid sensitive STIR sequence using two different segmentation methods and to analyze the association between the MR findings and disability and pain.MethodsTwenty-two patients (mean age 61 years, range 41–79 years) with medial femoro-tibial knee OA obtained MRI and filled out a WOMAC questionnaire at baseline and follow-up (median interval of 334 days). STIR, dynamic contrast enhanced-MRI (DCE-MRI) and fat saturated T1 post-contrast (T1 CE FS) MRI sequences were obtained. All STIR and T1 CE FS sequences were assessed independently by two readers for STIR-BMLs and contrast enhancing areas of BMLs (CEA-BMLs) using manual segmentation and computer assisted segmentation, and the measurements were compared. DCE-MRIs were assessed for the relative distribution of voxels with an inflammatory enhancement pattern, Nvoxel, in the bone marrow. All findings were compared to WOMAC scores, including pain and overall symptoms, and changes from baseline to follow-up were analyzed.ResultsThe average volume of CEA-BML was smaller than the STIR-BML volume by manual segmentation. The opposite was found for computer assisted segmentation where the average CEA-BML volume was larger than the STIR-BML volume. The contradictory finding by computer assisted segmentation was partly caused by a number of outliers with an apparent generally increased signal intensity in the anterior parts of the femoral condyle and tibial plateau causing an overestimation of the CEA-BML volume.Both CEA-BML, STIR-BML and Nvoxel were significantly correlated with symptoms and to a similar degree. A significant reduction in total WOMAC score was seen at follow-up, but no significant changes were observed for either CEA-BML, STIR-BML or Nvoxel.ConclusionsNeither the degree nor the volume of contrast enhancement in BMLs seems to add any clinical information compared to BMLs visualized by fluid sensitive sequences. Manual segmentation may be needed to obtain valid CEA-BML measurements.Electronic supplementary materialThe online version of this article (doi:10.1186/s12891-016-1336-9) contains supplementary material, which is available to authorized users.

The effect of intra-articular glucocorticosteroids and exercise on symptoms and bone marrow lesions in knee osteoarthritis: a secondary analysis of results from a randomized controlled trial

“…They are identified as poorly delineated areas of increased signal intensity in the subchondral bone marrow on fluid-sensitive MRI sequences 12,13 , preferably short tau inversion recovery (STIR)-sequences, T2-weighted or proton density weighted fat-suppressed fast spin echo sequences 14 . Even though BML areas enhance after contrast administration, no additional clinical information is gained by post-contrast sequences 15 . Due to their fluctuating nature 16 , BMLs may be potential biomarkers for monitoring disease status in clinical knee OA trials.…”

Quantitative and semi-quantitative assessment of synovitis on MRI and the relationship with symptoms in symptomatic knee osteoarthritis

“…Further, we measured the femoral condyle width across a total of four slices. While, ideally, femoral condyle width would be measured across all available slices, this was not pragmatic and our methods are in agreement with previous methods used to quantify relative values [ 40 , 41 ]. Further, we measured femoral condyle width from two points of the subchondral bone, which is in keeping with previous methods [ 27 ].…”

Effects of receptor activator nuclear factor κB gene polymorphisms on the susceptibility to knee osteoarthritis

“…It is well known that bone lesions are main pathological change in OA. [12] Thus, we hypothesized that genes associated with bone metabolism might affect OA risk.…”