Connective Tissue Degeneration in Age-Related Osteoarthritis Knee: Role of Inflammatory Mediators

Background: Osteoarthritis is a prevalent knee joint disorder causing cartilage degradation and subchondral bone changes, leading to pain, stiffness, and impaired movement. Inflammatory mediators play a crucial role in the pathogenesis of Knee OA causes cartilage degeneration. Method: A prospective study was conducted from January 2020 to December 2023, involving 132 patients diagnosed with age-related OA at the Department of Physical Medicine & Rehabilitation, Rajshahi Medical College Hospital. Blood samples were analyzed for inflammatory cytokines (TNF-α, IL-1β) and matrix metalloproteinases (MMP-3, MMP-13). Radiographic and clinical assessments were used to evaluate the activities of cartilage and bone changes. Results: In this study of 132 patients with age-related osteoarthritis (OA) Knee, 54% exhibited moderate to severe OA based on radiographic assessments, while 46% had mild OA. Elevated levels of Tumor Necrosis Factor-alpha (TNF-α) and Interleukin-1β (IL-1β) were found in 78% of the patients, with mean TNF-α levels at 56.3 ± 12.7 pg/mL and IL-1β at 48.9 ± 11.4 pg/mL in those with elevated mediators. These levels showed significant correlations with cartilage degradation and subchondral bone sclerosis (p < 0.01). Matrix Metalloproteinases (MMP-3 and MMP-13) were elevated in 65% of patients, with mean levels of 112.4 ± 25.3 ng/mL for MMP-3 and 89.2 ± 20.7 ng/mL for MMP-13, both correlating strongly with cartilage breakdown and subchondral bone changes (p < 0.01). Radiographic evaluations indicated severe cartilage degeneration in 54% of patients, correlating with high TNF-α and IL-1β levels, and subchondral bone sclerosis in 60% of patients, also associated with elevated inflammatory mediators. Conclusions: Inflammatory mediators, particularly TNF-α and IL-1β, are significantly associated with connective tissue degeneration in age-related OA.