Elbow joint effusion refers to swelling in the elbow joint due to a buildup of fluid. It results from inflammation and can happen for various reasons. Possible causes of elbow joint effusion include a ...

Water on the knee, or knee effusion, refers to the buildup of fluid in and around the knee joint. This condition leads to a painful, swollen knee and can be caused by various factors, including ...

Some amount of fluid around your knee is necessary — it helps cushion your bones and keeps the joint limber. But if too much fluid accumulates, it can lead to an effusion (or an abnormal collection of ...