Reduction in joint inflammation following administration of study medication. Physician's assessment of joint tenderness in patients receiving canakinumab 150 mg (a) or triamcinolone acetonide (TA) 40 mg (b) and physician's assessment of joint swelling in patients receiving canakinumab 150 mg (c) or triamcinolone acetonide 40 mg (d). Physicians assessed inflammation in the target joint using the following tenderness and swelling scales: tenderness rated as none, 'no pain'; mild, 'pain'; moderate, 'pain and winces'; severe, 'pain; winces and withdraws'; and swelling rated as none, 'no swelling'; mild, 'palpable'; moderate, 'visible'; and severe, 'bulging beyond the joint margins'. Percentages are rounded to one unit therefore numbers at each time point do not necessarily add to 100. TA, triamcinolone acetonide.