I have a large hard painful bump at the pisiform palmar side. It causes pain up my arm nearly to the elbow . It also causes pain up through the middle palmar side of my hand and tingling/numbness in the 4th and 5th finger (all on right hand). I have been told it was tendonitis and would get better. That didn t happen. Then told it was capsulitis and was given a cortisone shot which helped for about two days. Now the lump is larger and highly visible to the naked eye and the pain and tingling/numbness is worse. I also can no longer trust the hand to hold anything without shooting pain or open anything without the same. The hand is becoming noticeably weaker and I ve started having trouble controlling the movement at times when it is very sore. I am scheduled to have an MRI this coming week and want to be well informed before going of what it could possibly be but can t seem to find any helpful information anywhere.