Arthrocentesis takes 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, such as the knee or shoulder.


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Reasons for Procedure

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, medication may be injected into the joint space after the fluid has been taken out.

    Possible Complications

    Problems from the procedure are rare, but all procedures have some risk. Your doctor will review potential problems, like:

  • Infection of the joint
  • Bleeding into the joint
  • Increased pain
  • Some factors that may increase the risk of complications include:

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

    Prior to Procedure

    You will be asked about your medical history. A physical exam will be done, including an examination of the joint.

    Imaging tests to help view internal body structures may include:

  • X-ray
  • MRI scan
  • Anesthesia

    You may be given local anesthesia. This numbs the area where the needle will enter the joint.

    Description of the Procedure

    The area where the needle will be inserted will be cleaned. Next, a needle attached to a syringe will be inserted into the fluid-filled joint cavity. The fluid will be drawn into the syringe. After this, medication may be injected into the joint through the needle. After the needle is removed, pressure will be put on the spot over the joint. A bandage will be placed over the area.

    How Long Will It Take?

    About 5-10 minutes

    How Much Will It Hurt?

    You may feel stinging or burning if local anesthesia is injected into the area.

    Post-procedure Care

    When you return home after the procedure, be sure to follow your doctor's instructions.

    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 site
  • Pain that is not relieved by the medication you have been given
  • If you think you have an emergency, call for emergency medical services right away.