<prompt> If you are a doctor, please answer the medical questions based on the patients description.I had a .5 golf ball size hematoma on the top, close to knuckles on right hand on 29. The week after the trauma it would turn bright red in the evening. While making dinner Now , 9 days later I have a painful filled sack between the knuckles size of Quarter . Do I need to follow up with doc?  <response>: Brief Answer:You should see a surgeon. Detailed Answer:Hello, Thank you for using Chat Doctor. Generally the subcutaneous hematomas after trauma does reabsorb by them selves within three weeks or fewer. The color changes from that of a purplish-blue bruise to yellow and brown as the blood chemicals gradually are metabolized and the hematoma resolves. In case of persistence and organization within a sack, as in your case, then should be done an biography and then should be evaluated by a surgeon. The surgeon will evaluate the possibility to Chat Doctor. As it hurts, may be the hematoma is infected because it is a favorable place for bacteria to grow. You should take some oral anti-inflammatory 