by EBSCO Medical Review Board
(Joint Aspiration)


Arthrocentesis takes joint fluid out using a needle. It can be done in most of the joints in the body. It is usually done on large joints like the knee or shoulder.

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Reasons for Procedure

It is done to:

  • Find out why a joint is painful, swollen, or is filled with fluid
  • Ease pain and allow the joint to move better
  • Diagnose the type of arthritis in a joint
  • Confirm a diagnosis of infection
  • Check for crystals in the joint fluid, which could be a sign of gout

Some people may have medicine injected in the joint space after the fluid has been taken out.

Possible Complications

Problems are rare, but all procedures have some risk. The doctor will go over some problems that could happen, such as

  • Excess bleeding
  • Problems from anesthesia, such as wheezing
  • Infection
  • Increased pain
  • Damage to nearby structures

Things that may raise the risk of problems are:

  • An infection in the body
  • Bleeding problems
  • Use of blood thinners

What to Expect

Prior to Procedure

The surgical team may meet with you to talk about:

  • Anesthesia options
  • Any allergies you may have
  • Current medicines, herbs, and supplements that you take and whether you need to stop taking them before surgery
  • Whether you need a ride to and from surgery


You will be given local anesthesia. The area will be numbed.

Description of the Procedure

A needle attached to a syringe will be inserted into the joint. Fluid will be pulled into the syringe. Medicine may also be injected into the joint through the needle. The needle will be removed. A bandage will be put on the site.

How Long Will It Take?

About 5 to 10 minutes

How Much Will It Hurt?

Pain and swelling are common in the first 2 days. Medicine and home care can help.

Post-procedure Care

At the Care Center

Right after the procedure, the staff may:

  • Give you pain medicine
  • Raise the joint to ease swelling
  • Apply ice to the joint
At Home

It will take a few weeks for the incision and muscles to fully heal. Physical activity may need to be limited during recovery. You may need to ask for help with daily activities and delay return to work for a few weeks.

Call Your Doctor

Call the doctor if you are not getting better or you have:

  • Signs of infection, such as fever and chills
  • Redness, swelling, increasing pain, excessive bleeding, or any discharge from the site
  • Pain that does not get better with medicine

If you think you have an emergency, call for medical help right away.


Arthritis Foundation 

National Institute of Arthritis and Musculoskeletal and Skin Diseases 


The Arthritis Society 

Canadian Orthopaedic Association 


Joint aspiration (arthrocentesis). Rady Children's Hospital San Diego website. Available at: Accessed September 28, 2020.

Synovial fluid analysis. EBSCO DynaMed website. Available at: Accessed September 28, 2020.

Synovial fluid analysis. Lab Tests Online—American Association for Clinical Chemistry website. Available at: Accessed September 28, 2020.

Tercic D, Bozic B. The basis of the synovial fluid analysis. Clin Chem Lab Med 2001; 39(12):1221-1226.

Revision Information