When is arthrocentesis contraindicated?
When the clinical indication for obtaining synovial fluid is strong, such as in the patient with suspected septic arthritis, there is no absolute contraindication to joint aspiration. Relative contraindications include bleeding diatheses, such as hemophilia, anticoagulation therapy, or severe thrombocytopenia; however, these conditions can be frequently treated or reversed before arthrocentesis. Cellulitis overlying a swollen joint can make the approach to the joint space difficult, but this rarely precludes the ability to perform the procedure. Bacteremia confers a small risk to seeding a joint with microorganisms during the arthrocentesis.