These sudden internal growths, manifest quickly, usually while sleeping or sitting in a chair watching TV. They feel hard as bone and are somewhat painful. The pain makes me aware of them. It can be one lump or several and may occur on either hand but, always on one hand at a time, usually the right hand. The raised area is mostly forward and adjacent to the knuckle. The swelling happens more quickly than it goes away but, usually goes away in a day or so. The pain is of short duration and happens when the swelling first is noticed and at its largest. The pain subsides in about an hour or less. The swelled area seems to hit a high point and then settle down some. This has happened half a dozen times or so. I am of retirement age if it helps.