Fast Five Quiz: Can You Answer These Challenging Orthopedic Questions?

James W. Pritchett, MD; Craig C. Young, MD


March 14, 2017

No absolute contraindications for knee arthrocentesis are recognized. Relative contraindications include the following:

  • Cellulitis overlying the joint: If arthrocentesis is performed, the patient should be admitted for the administration of intravenous antibiotics, even if the synovial fluid is not suggestive of infectious arthritis;

  • Skin lesion or dermatitis overlying the joint;

  • Known bacteremia;

  • Adjacent osteomyelitis;

  • Uncontrolled coagulopathy; and

  • Joint prosthesis: Preferably, a joint prosthesis is tapped by an orthopedist.

The presence of noninflammatory joint fluid helps distinguish osteoarthritis from other causes of joint pain. Other synovial fluid findings that aid in the differentiation of osteoarthritis from other conditions include negative Gram stains and cultures as well as the absence of crystals when fluid is viewed under a polarized microscope.

Laboratory studies are not indicated for patellofemoral joint syndromes, unless there is a need to rule out other potential causes, such as systemic, inflammatory, or metabolic disease.

For more on knee arthrocentesis, read here.


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