What are Arthrocentesis?

This is a procedure to take joint fluid out of a joint using a sterile needle. This can be done in most of the joints in the body, but it is usually done on larger ones (eg, knee, shoulder).

Arthrocentesis © 2009 Nucleus Medical Media, Inc.

Arthrocentesis is done to:

• Find out why a joint is painful, swollen, or fluid-filled
• Drain fluid out of a swollen joint to decrease pain and increase your ability to move the joint
• Diagnose the specific type of arthritis occurring within a joint
• Confirm a diagnosis of infection in the joint
• Check for crystals in the joint fluid, which could be a sign of gout

In some cases, the doctor may inject medicine (eg, cortisone) into the joint space after the fluid has been taken out.

Possible Complications

Complications are rare, but no procedure is completely free of risk. If you are planning to have arthrocentesis, your doctor will review a list of possible complications, which may include:

• Infection of the joint
• Bleeding into the joint
• Increased pain
• Allergic reaction

Some factors that may increase the risk of complications include:

• Infections on the skin
• Recent fever or infection
• Bleeding disorder
• Use of blood thinners

Be sure to discuss these risks with your doctor before the procedure.

Call Your Doctor

After arriving home, contact your doctor if any of the following occurs:

• Signs of infection, including fever and chills
• Redness, swelling, increasing pain, excessive bleeding, or any discharge from the...