What Causes Severe Knee Pain After Treatment For Fractured Talus?

Hello, my name is Mary, I recently just got over a fractured talus bone on my left ankle. I have been feeling pretty good so I strarted walking again for exercise and started jogging as well, and now my left knee hurts so bad i can barely walk on it without pain. what could this be? I dont see any swelling. Ive been taking tylenol with ibuprofen around the clock. and it still hurts to put any pressure on it?