Synovial fluid analysis

A sample of synovial fluid is needed for this test. Synovial fluid is normally a thick, straw-colored liquid found in small amounts in joints. After the skin around the joint is cleaned, the health care provider inserts a sterile needle through the skin and into the joint space. Fluid is then drawn through the needle…

Normally, no special preparation is needed. Tell your provider if you are taking a blood thinner, such as aspirin, warfarin (Coumadin), or clopidogrel (Plavix). These medicines can affect test results or your ability to have this test.

Most often, the provider will first inject numbing medicine into the skin with a small needle, which will sting. A larger needle is then used to draw out the synovial fluid. This test may also cause some discomfort if the tip of the needle touches bone. The procedure usually lasts less than 1 to 2 minutes. It may be…

The test can help diagnose the cause of pain, redness, or swelling in joints. Sometimes, removing the fluid can also help relieve joint pain. This test may be used when your provider suspects: Bleeding in the joint after a joint injury Gout , other types of crystal disease, and arthritis Infection in a joint

Abnormal joint fluid may look cloudy or abnormally thick. The following found in joint fluid can be a sign of a health problem: Blood -- injury in the joint or bleeding problem of the body Pus -- infection in the joint Too much joint fluid -- osteoarthritis or cartilage, ligament, or meniscus injury Evidence of gout…

Risks of this test include: Infection of the joint -- unusual, but more common with repeated aspirations Bleeding into the joint space

Ice or cold packs may be applied to the joint for 24 to 36 hours after the test to reduce the swelling and joint pain. Depending on the exact problem, you can probably resume your normal activities after the procedure. Talk to your provider to determine what activity is most appropriate for you.

El-Gabalawy HS, Tanner S. Synovial fluid analyses, synovial biopsy, and synovial pathology. In: Firestein GS, Budd RC, Gabriel SE, McInnes IB, O'Dell JR, eds. Firestein & Kelley's Textbook of Rheumatology . 11th ed. Philadelphia, PA: Elsevier; 2021:chap 56. Pisetsky DS. Laboratory testing in the rheumatic diseases.…