These 10 animal facts will amaze you. A swollen finger can be caused by a number of things, including injuries, infections, or even repetitive motion. If a finger is broken or infected, it is important to seek medical attention instead of trying to deal with problem yourself. If it is jammed or twisted, but not broken, and does not have an open wound, then the Rest, Ice, Compression, Elevation (RICE) method is generally the best treatment.