What is a joint aspiration?
A joint aspiration is a procedure whereby a sterile needle and syringe are used to drain fluid from the joint. Joint aspiration is typically performed as an office procedure or at the bedside of hospitalized patients. Joint aspiration is medically referred to as arthrocentesis.
What is the purpose of joint aspiration?
Joint aspiration is used to obtain joint fluid for examination in the laboratory. Analysis of joint fluid can help to define causes of joint swelling or arthritis, such as infection, gout, and rheumatoid disease. Joint fluid can be tested for white cell count, crystals, protein, glucose, as well as cultured to detect infection. Each of these laboratory parameters can be helpful in defining the cause of a particular form of arthritis.
Joint aspiration can also be helpful in relieving joint swelling and pain. Removal of joint fluid that is inflamed can also remove the white blood cells within that are sources of enzymes that can be destructive to the joint. Occasionally, cortisone (an antiinflammatory medication) or hyaluronic acid derivatives (a synthetic joint lubricant, approved for use in the knee only) are injected into the joint during the joint aspiration in order to rapidly relieve joint inflammation and further reduce symptoms.