Causes of Swollen Finger Joints and How to Treat Them
Swollen finger joints are frequently the result of inflammation caused by an infection, injury, or disease. The swelling may be due to a chronic (persistent or recurrent) condition, like osteoarthritis, rheumatoid arthritis, or gout. Or, it may be due to acute (sudden and short-lasting), non-arthritis causes, like a fracture, infected cut, or a "jammed finger."
Source: Verywell health
