The Draining knee procedure is often conducted when there is excess fluid accumulation around the knee joint as a result of inflammation, infection, or trauma. Knee Aspiration is a medical procedure during which, a needle is inserted into the knee joint to remove fluid. It can also be known as “Knee Arthrocentesis”, 'joint aspiration', or 'fluid aspiration'. The collected fluid is then analyzed for any signs of infection, inflammation, or other abnormalities.

The main objective of knee aspiration is identifying and treating conditions including arthritis, gout, bursitis, and tendinitis. In some cases, it may also be used to help diagnose other conditions such as infections or cancer. Knee aspirations are usually done in an outpatient setting and can be done quickly.