Hi, I keep getting a recurring bruise on the back of my calf about 3 inches below the back of my knee. It started about 1 1/2 months ago. It was a dark purple with black spots in it. I know I didn't bump it. It took almost a full month to go away, but now it's back. It is very tender to the touch and feels like there is a very small knot in it. Any ideas as too what is causing this? I am 29, female with chron's. I had heart surgery in 2007 for SVT.