A synovial biopsy is the removal of a piece of tissue lining a joint for examination. The tissue is called the synovial membrane.
Biopsy - synovial membrane
How the Test is Performed
The test is done in the operating room, usually during an arthroscopy or small incision.
After anesthesia, an instrument called a trocar is inserted into the joint space. This tool helps push fluid in and out of the area. A biopsy grasper is inserted through the trocar and turned to cut out a tissue segment.
The tools are removed. A bandage is applied.
How to Prepare for the Test
Tell your health care provider:
- If you are pregnant
- If you ever had a problem with anesthesia
- If you have any drug allergies
- If you have bleeding problems
- What medications you are taking (including any herbal medicines and supplements)
How the Test will Feel
With the local anesthetic, you will feel a prick and a burning sensation. As the trocar is inserted, there will be some discomfort. If the surgery is performed under regional or general anesthesia, you will not feel the procedure.
Why the Test is Performed
Synovial biopsy helps diagnose gout and bacterial infections, or rule out other infections. It can be used to diagnose autoimmune disorders like rheumatoid arthritis, or uncommon infections like tuberculosis.
The synovial membrane structure is normal.
What Abnormal Results Mean
Synovial biopsy may identify the following conditions:
- Chronic synovitis
- Coccidioidomycosis (a fungal infection)
- Fungal arthritis
- Hemochromatosis (abnormal buildup of iron deposits)
- Synovial cancer
The test may help diagnose rheumatoid arthritis, lupus, and other autoimmune diseases.
There is a very slight chance of infection and bleeding. Rarely, there is a chance of the needle striking a nerve or blood vessel.
You will need to keep the wound clean and dry until your doctor or nurse says it is okay to get it wet.
El-Gabalawy HS. Synovial fluid analysis, synovial biopsy, and synovial pathology. In: Firestein GS, Budd RC, Harris ED Jr., et al, eds. Kelley's Textbook of Rheumatology. 8th ed. Philadelphia, PA: Saunders Elsevier; 2008:chap 48.
Reviewed By: C. Benjamin Ma, MD, Assistant Professor, Chief, Sports Medicine and Shoulder Service, UCSF Department of Orthopaedic Surgery, San Francisco, CA. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the A.D.A.M. Editorial team.