ObjectiveTo investigate the correlation of synovial fluid uric acid, the serum and synovial fluid interleukin (IL)-1β, IL-6, and tumor necrosis factor (TNF)-α with knee osteoarthritis (KOA). MethodsThe clinical data of 130 patients with KOA treated between January and December 2013 and 30 patients with gouty arthritis (GA) treated at the same period were collected. The clinical symptoms, Western Ontario and McMaster Universities Osteoarthritis Index score, the serum and synovial fluid IL-1β, IL-6, and TNF-α, uric acid levels, radiographic joint stenosis score, and bone hyperplasia score of the patients were compared using t-test analysis and Spearman correlation analysis. ResultsIn the KOA group, the synovial fluid uric acid and joint stenosis score (r=0.31, P=0.037), bone hyperplasia score (r=0.38, P=0.027) were positively correlated; serum and synovial fluid uric acid gradient and hypnalgia were positively correlated (r=0.34, P=0.031); the synovial fluid IL-6 and joint stenosis score (r=0.33, P=0.029), bone hyperplasia score (r=0.37, P=0.032) were positively correlated; the synovial fluid IL-1β and joint stenosis score (r=0.39, P=0.023), bone hyperplasia score (r=0.34, P=0.034) were positively correlated; and the synovial fluid uric acid and IL-1β (r=0.26, P=0.003), IL-6 (r=0.21, P=0.016) were positively correlated. ConclusionSynovial uric acid, IL-1β and IL-6 play a role in the inflammatory progress of knee osteoarthritis.