EPCR deficiency attenuates synovitis following hemarthrosis in FVIII^−/− mouse joint. Joint bleeding in WT, FVIII^−/−, EPCR⁺⁺FVIII^−/−, and EPCR^−/−FVIII^−/− mice was induced by needle injury, and the mice were treated with a single or 3 doses of rFVIIa or left untreated as described in the Figure 1 legend. (A) Synovitis score was determined as described in "Materials and methods," and a score of 11 was maximum. (B) IL-6 levels in synovial fluids. (C) Representative images of uninjured and injured knees. *P < .05; **P < .01; ns, no statistically significant difference.