What Causes Swelling Of Fingers And Knuckles And Gel Like Discharge?

I have had swelling on different parts of my fingers, knuckles ect.. six months ago my right thumb's swelling was getting larger I punctured the swelling and got out a jelly like clear fluid but it didn't go away. instead it got a bacterial infection and grew ohh?? four times it size. I did a round of Keflex then a round of bactrum. but the two knuckles in my thumb still won't bend and the swelling hasn't gone all the away. what can I do? more soaking? please help!!!