What Is Joint Aspiration?
Since different medical conditions can have similar symptoms and because there are more than 100 arthritic conditions, it can sometimes be difficult to diagnose specific types of arthritis. Joint aspiration, also known as arthrocentesis, can be used to draw fluid from an inflamed joint so it can be analyzed by your doctor or a laboratory technician to determine the type or cause of your arthritis. The procedure can also be used to remove enough built-up fluid to reduce pressure, relieve painful joints, and promote healing in the joint area. Fluid can be drawn from shoulders, elbows, wrists, hips, knees, ankles and other joints.

The Procedure
Unless you are already in the hospital for some reason, joint aspiration is usually performed in a doctor's office. Local anesthesia is used to numb the area prior to injection. The skin around the injection site is cleaned, and a needle with a syringe attached is injected into the space that surrounds the joint. If the aspiration is being done for diagnostic reasons, the needle may be a little larger than if it is being performed strictly to reduce fluid build-up. This is to help insure that only one withdrawal is needed. Once the fluid is removed, a simple dressing or bandage is applied to the area. The procedure is relatively simple and complications are rare.

The Findings
Joint aspiration can be used to determine if rheumatoid (joint and connective tissue) disease, infection, or gout (a disease usually characterized by inflammatory arthritis) is causing swelling in your joints. The aspirated fluid is analyzed for crystal content, blood cell count, and the presence of destructive enzymes. The color, translucency and viscosity (thickness) of the fluid can help determine the degree of inflammation. Once the fluid is analyzed and the cause and degree of swelling are determined, specific treatment can be planned.

The Treatment
Joint aspiration can be used as a treatment when a large quantity of fluid surrounds the joint, causing pressure and pain. Under these circumstances, once the excess fluid is removed, your doctor may decide to inject medication into your joint. For instance, cortisone (corticosteroid) injections are often used to treat arthritis in the knee and joint pain elsewhere in the body because corticosteroids reduce inflammation and offer fast relief of pain.

 

Sources:

American College of Rheumatology. Joint Aspiration. Web. 27 April 2013.
http://www.rheumatology.org/practice/clinical/patients/diseases_and_conditions/jointinjection.pdf

Beaumont Health System. Joint Aspiration. Web. 27 April 2013.
http://www.beaumont.edu/health-library/P07680

Fields TR, Berman, JR. "HSS Manual Ch. 8-Arthrocentesis, Intraarticular Injection and Synovial Fluid Analysis." Hospital for Special Surgery. Web. Page posted 14 April 2006. Accessed 27 April 2013.
http://www.hss.edu/professional-conditions_hss-manual-ch8-arthrocentesis-intraarticular-injection-synovial.asp#Joint-Specific_Techniques