A synovial biopsy is the removal of a piece of tissue lining a joint. The tissue is called the synovial membrane.
Biopsy - synovial membrane
How the test is performed
The test is usually done in the operating room with the use of arthroscopy.
The health care provider will inject a numbing medicine (local anesthetic) into the area. 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. The biopsy site is cleaned. Pressure and a bandage are applied.
How to prepare for the test
Tell your health care provider:
- If you are pregnant
- 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.
Why the test is performed
Synovial biopsy helps diagnose gout, bacterial infections, or other infections, and may suggest the presence of inflammatory conditions such as autoimmune disorders.
The synovial membrane structure is normal.
What abnormal results mean
Synovial biopsy may identify the following conditions:
- Coccidioidomycosis (a fungal infection)
- Fungal arthritis
- Hemochromatosis (abnormal accumulation of iron deposits)
- Synovial cancer
The test may help diagnose rheumatoid arthritis and other autoimmune diseases.
What the risks are
There is a very slight chance of infection and bleeding. Rarely, there is a chance of the needle striking a nerve or blood vessel.
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: Linda J. Vorvick, MD, MEDEX Northwest Division of Physician Assistant Studies, University of Washington School of Medicine; and C. Benjamin Ma, MD, Assistant Professor, Chief, Sports Medicine and Shoulder Service, UCSF Department of Orthopaedic Surgery. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.