The large knuckle on my pinkie has a bump on the side next to ring finger. It is painful. Wonder if this is osteoarthritis? I'm 50 years old and spend quite a bit of time on computer. Could this be the problem? It's only on that one pinkie finger.
I have psoriatic arthritis and I have a bump on the inside of my left pinky knuckle. All my knucles are very sore and thick, but my pinky is the only one with an obvious lump. I would recommend going to see your doctor so they can evaluate your symptoms and maybe take x-rays.