Osteophyte formation, destruction of the articular surface and synovial tissue analysis. Analysis of (a) osteophyte formation, (b) destruction of the articular surface and (c) analysis of synovial tissue. The knee joints were treated by administration of 2-methoxyestradiol (2ME2) in Balb/C mice or of dimethyloxaloylglycine (DMOG) in STR/ORT mice. Bars show the mean ± standard deviation. *P <0.05, **P <0.01 versus untreated control joint.