Tuberculous synovitis in the elbow joint is extremely rare in developed countries. We describe a 68-year-old man who had had a gradually enlarging mass over the volar side of the left proximal forearm near the elbow joint for 4 months. Plain roentgenograms of the diseased elbow showed early osteoarthritic change. Magnetic resonance imaging revealed diffuse synovitis with a large 8 x 8 cm extra-...