Evolution of synovitis in osteoarthritic knees and its association with clinical features.
To investigate the course of synovitis on contrast-enhanced magnetic resonance images (CE-MRI) in osteoarthritic knees over 2 years, and its association with pain and cartilage deterioration.



Consecutive patients (n = 39, mean age 61 years, 79% woman, median (range) body mass index (BMI) 29 (24-48) kg/mm2) with clinical osteoarthritis (OA) were included. Baseline and follow-up CE-MRI (3 T) were scored paired in chronological order for synovitis (semi-quantitatively at 11 sites (range 0-22)), cartilage deterioration and bone marrow lesions (BMLs) (semi-quantitatively according to Knee Osteoarthritis Scoring System (KOSS)). Changes in sum scores were calculated. Cartilage deterioration was defined as change of ≥2 above the smallest detectable change (SDC). Pain was assessed by standardized questionnaires. Analysis of covariance (ANCOVA) and linear regression models were used to investigate association between synovitis change and cartilage deterioration and between synovitis change or cartilage deterioration and change in pain.



The total synovitis score did not change over 2 years (mean change 0.2 (standard deviation (SD) 3.2)), although changes in individual patients were observed. Cartilage deterioration was observed in 51% of patients. Synovitis change score was lower in patients without compared to patients with cartilage deterioration, taking BML change in account (mean difference -2.1 (-4.1 to -0.1)). Change in synovitis was not associated with change in pain, whereas cartilage deterioration was associated with change in Intermittent and Constant OsteoArthritis Pain (ICOAP) constant pain in adjusted models (unstandardised coefficient (B) (95% confidence interval (CI)) 2.8 (0.4-5.3)).



In individual patients synovitis fluctuates during disease course. Synovitis change was not associated with change in pain. Increase in synovitis is associated with cartilage deterioration, suggesting a role for synovitis as a target for disease-modifying treatment.
Department of Rheumatology, Leiden University Medical Centre, Leiden, The Netherlands. Electronic address: badelog@hotmail.com.
B J E
BJ
de Lange-Brokaar
Department of Rheumatology, Leiden University Medical Centre, Leiden, The Netherlands.
A
A
Ioan-Facsinay
Department of Rheumatology, Leiden University Medical Centre, Leiden, The Netherlands.
E
E
Yusuf
Department of Radiology, Leiden University Medical Center, Leiden, The Netherlands.
H M
HM
Kroon
TNO, Leiden, The Netherlands.
A-M
AM
Zuurmond
Janssen, Pharmaceutical Companies of Johnson & Johnson, Pennsylvania, USA.
V
V
Stojanovic-Susulic
Department of Orthopaedics, Leiden University Medical Center, Leiden, The Netherlands.
R G H H
RG
Nelissen
Department of Radiology, Leiden University Medical Center, Leiden, The Netherlands.
J L
JL
Bloem
Department of Rheumatology, Leiden University Medical Centre, Leiden, The Netherlands; Department of Clinical Epidemiology, Leiden University Medical Center, Leiden, The Netherlands.
M
M
Kloppenburg
D001853:Bone Marrow; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D020370:Osteoarthritis, Knee; D010146:Pain; D013585:Synovitis
BML; Cartilage; MRI; Osteoarthritis; Progression; Synovitis