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Updated: Oct 25, 2026
A Pre-Clinical Model of Synovitis Using Ex vivo Human Synovial Tissue with Preserved Function and Architecture
Published on: March 20, 2026
Synovial oxidative stress biomarkers are not associated with radiological severity in knee osteoarthritis: a
Hakan Yolaçan1, Hüseyin Erdal2, Serkan Güler3
1Department of Orthopaedics and Traumatology, Faculty of Medicine, Aksaray University, Aksaray, Turkey. hakanyolacan@aksaray.edu.tr.
Objective:
This prospectively enrolled cross-sectional study aimed to evaluate the relationship between synovial fluid oxidative stress parameters and radiographic severity in patients with knee osteoarthritis and to determine whether these biomarkers reflect radiographic stage.
Methods:
A total of 98 patients aged 50 years and older with primary knee osteoarthritis were prospectively enrolled in this cross-sectional study. Radiological severity was classified using the Kellgren-Lawrence (KL) grading system as early-stage (KL grades 1-2) and late-stage (KL grades 3-4). Clinical severity was evaluated using the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) and Visual Analog Scale (VAS). Synovial fluid samples were analyzed for total thiol (TT), native thiol (NT), disulfide (DS), total antioxidant status (TAS), total oxidant status (TOS), oxidative stress index (OSI), and glutathione peroxidase (GPx) levels. Logistic regression, receiver operating characteristic (ROC) analysis, correlation analysis, and analysis of covariance (ANCOVA) were performed.
Results:
WOMAC pain, stiffness, function, total scores, and VAS scores were significantly higher in patients with late-stage osteoarthritis (p < 0.001). Among oxidative stress parameters, only total oxidant status levels were significantly higher in late-stage osteoarthritis (p = 0.007), whereas TT, NT, DS, TAS, OSI, and GPx levels did not differ significantly between early-stage and late-stage osteoarthritis groups. In multivariable logistic regression analysis, WOMAC total score and VAS score were independently associated with late-stage osteoarthritis, whereas oxidative stress biomarkers were not. ROC analysis showed excellent discriminative performance for WOMAC total and VAS scores, whereas oxidative stress parameters showed poor to moderate discriminative performance. Correlation and ANCOVA analyses demonstrated no significant association between most oxidative stress parameters and radiological osteoarthritis stage.
Conclusion:
Synovial oxidative stress biomarkers are not reliable indicators of radiological severity in knee osteoarthritis, although total oxidant status may increase in advanced disease. Clinical severity scores showed the strongest cross-sectional association with radiographic stage. These findings suggest that oxidative stress may contribute to the pathophysiology of knee osteoarthritis but does not adequately reflect radiographic disease severity.
