Joint fluid analysis
is a test to look at joint fluid under a microscope for problems such as
inflammation, or bleeding. The test can help find the
joint pain or swelling.
Normally, only a
small amount of joint fluid is found in a joint. Joint fluid acts as a
lubricant for the joint and cushions joint structures. If you have a joint
problem, you may have more fluid in your joint and your joint may become
swollen, stiff, and painful.
A sample of joint fluid can be taken
from any joint in your body. The joint fluid is then analyzed in a lab to look
for inflammation, infection, gout, pseudogout, or bleeding.
Why It Is Done
Joint fluid analysis is done to find
inflammation, infection, gout, or pseudogout. Removing some of the joint fluid
may also relieve pain caused by the buildup of fluid in your joint.
How To Prepare
Tell your doctor if you:
- Have taken aspirin recently.
taking any medicines that can delay blood clotting, including nonsteroidal
anti-inflammatory drugs (NSAIDs, such as ibuprofen, naproxen, or etodolac) or
- Are allergic to any medicines, including
- Have any bleeding problems.
- Are or might
Talk to your doctor about any concerns you have about the
need for the test, its risks, how it will be done, or what the results will
mean. To help you understand the importance of this test, fill out the
medical test information form(What is a PDF document?).
How It Is Done
Joint fluid analysis takes about 20
minutes and can be done in your doctor's office, clinic, operating room, or
emergency room. Depending on which joint will be examined, you may be asked to
undress and put on a hospital gown. You will sit or lie down on an examining
Your doctor will examine the joint to determine where the
needle should be inserted. The skin over the joint area will be cleaned with
antiseptic solution. A
local anesthetic is often injected into the skin over
the joint. For young children, a
sedative may also be given.
A long, thin
needle is slowly inserted in the joint area. A syringe attached to the needle
is used to remove a sample of joint fluid. Samples of the fluid may be put in
special tubes or containers and sent to the lab. A cortisone shot may be given
into the joint before the needle is removed, to help keep fluid from building up again.
A tight (pressure)
bandage will be placed over the site to reduce swelling and bruising. An
elastic bandage may also be wrapped around your joint, such as your knee, to