I have a hard, puss filled knot on my back from the site of where I recieved an epidural about seven years ago. There has always been a small hard bump. It has become bothersome in the past week and is the size of a half dollar. My husband tried getting it to decrease in size by squeezing puss from it. It worked, but just an hour later it has increased in size again. The discharge is thick and smelly.