Clinical effects of lipopolysaccharide-induced joint inflammation. (a) Lameness grade, (b) effusion score and (c) carpal circumference following induction of synovitis in the intercarpal joints of horses (n = 6). Inflammation was induced at t = 0 by intra-articular injection of 0.5 ng Escherichia coli lipopolysaccharide. Data presented as the mean ± standard error of the mean. *P < 0.05, **P < 0.01, ***P < 0.001 compared with baseline (t = 0).