An arthrocentesis is a minor surgical procedure also referred to as a joint aspiration. The procedure can be performed on any joint. There risks involved are mainly small, and for most patients this procedure will be done on an outpatient basis.
Why is This Procedure Done?
The purpose of this procedure is to get fluid for further examination. By analyzing this fluid, a doctor can often determine whether or not a patient has arthritis, rheumatoid arthritis, gout, an infection, or if their swollen joint is caused by another medical condition. This procedure is also used to determine exactly what the cause of a specific type of arthritis is. This procedure may be used to administer corticosteroids and to remove pain-causing fluid.
What is the Required Preparation?
Patients may be asked to shave the joint and the area around prior to have an arthrocentesis. The area of the joint being aspirated will be cleaned by a nurse prior to the procedure. Patients taking blood thinners should consult their physician because they may need to adjust their dosage or refrain from these medications for a few days before the procedure to minimize the risk of bleeding.
How is This Procedure Performed and What is Involved?
The doctor will begin the joint aspiration by numbing it with a local anesthetic. He will either use a topical freezing liquid, an injectable numbing medication, and sometimes both. Once the area is numb, a needle (with attached syringe) will be inserted into the joint. The fluid will then be aspirated. If the patient is also receiving a corticosteroid injection, they will receive after the fluid has been aspirated.
What are the Risks?
Complications are not common with this procedure. However, the possible complications and risks include loss of skin pigment, a little bleeding into the joint, and local bruising. A serious, but rare complication of this procedure is a joint infection. If a corticosteroid was injected, there are additional risks, but these are also uncommon. They include aggravation of a current infection, joint inflammation, increased blood sugar, and pigment shrinkage or loss.
What is the Recovery Like?
After the procedure, the area will be cleaned and a small Band-Aid or dressing will be applied to the area. The patient will then be sent home. The patient may experience some discomfort, bruising, and soreness for a few days. If these worsen or persist, the patient should contact their physician.
How are the Results Used?
The fluid that is aspirated may be sent to a lab for further analysis. The fluid may be tested for infection, white cell count, glucose, and protein. The tests will be conducted to help determine the cause of the swelling or the cause of a specific type of arthritis.
MedicineNet. (2009). Arthrocentesis. Retrieved on October 23, 2009 from Website: https://www.medicinenet.com/joint_aspiration/article.htm