Which finding might be seen in PVNS on joint aspiration?

Which finding might be seen in PVNS on joint aspiration?

• A. Clear serous fluid
• B. Pus
• C. Bloody fluid
• D. Chylous fluid

Answer: (C)

PVNS involves a proliferative synovium with numerous fragile blood vessels, so recurrent bleeding into the joint is common. On aspiration this produces hemorrhagic, blood-stained fluid rather than clear serous fluid, pus, or milky/chylous fluid. The other fluid types point to different processes—clear serous can occur with noninflammatory effusions, pus indicates septic arthritis, and chylous fluid reflects lymphatic obstruction. So bloody fluid best fits PVNS on joint aspiration.