Ruan G, et al. - In patients with knee osteoarthritis (OA), researchers examined the cross-sectional associations between serum levels of S100A8/S100A9 and the outcomes. Study participants were 141 subjects with clinical knee OA. To evaluate joint symptoms, Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) score were used. A positive association was found between serum levels of S100A8/S100A9 and increased knee symptoms, cartilage defects and serum cartilage degradation enzymes in knee OA patients, implying that S100A8/S100A9 might have a role to play in knee OA.