Features of Early Osteoarthritis and Synovitis against the Background of Metabolic Syndrome: A Cross-Sectional Study

Abstract

Background: Early knee osteoarthritis may present with pain, stiffness, and functional limitation despite minimal radiographic changes. Metabolic syndrome may contribute to a more symptomatic and inflammatory disease pattern. Objective: This cross-sectional study evaluated the clinical, functional, anthropometric, laboratory-inflammatory, and instrumental features of early knee osteoarthritis associated with metabolic syndrome, with particular attention to synovitis. Methods: The study included 64 patients aged 35–60 years with early knee osteoarthritis. Thirty-eight patients had metabolic syndrome and 26 did not. Pain intensity was assessed using the visual analogue scale, and functional status and health-related quality of life were evaluated using WOMAC and KOOS indices. Body mass index, waist circumference, systemic inflammatory markers, cartilage oligomeric matrix protein, and knee-joint imaging findings were assessed. Results: Patients with metabolic syndrome had higher pain intensity, worse WOMAC scores, lower KOOS values, and more frequent synovitis than patients without metabolic syndrome. They also had higher body mass index and waist circumference values, while arterial hypertension and diabetes mellitus were observed only in this group. Interleukin-6, cartilage oligomeric matrix protein, and C-reactive protein levels were significantly elevated in the metabolic syndrome group, indicating greater inflammatory activity and cartilage matrix turnover. Conclusion: Early knee osteoarthritis associated with metabolic syndrome showed a metabolic-inflammatory pattern characterised by more pronounced symptoms, synovial involvement, and increased cartilage degradation markers. Comprehensive metabolic and inflammatory assessment may support early diagnosis and individualised management.