Joint Fluid Analysis: Components and Results

Joint Fluid Analysis helps determine the condition of the joint and diagnose joint-related disorders, such as joint inflammation, joint pain, and joint swelling. Some of the disorders may develop to permanently damage the joint. So, the results matter a lot.


Things you need to know before the test: in order to collect the joint fluid (synovial fluid) sample, the doctor may insert a needle into the joint space. In other words, it may sting.

The joint fluid analysis is composed of:

  • Physical characteristics: especially the color.
  • Chemical tests: glucose levels, protein levels, uric acid levels, etc.
  • Microscopic examination: to examine the presence of microbes and crystals.
  • Total cell counts: especially the amount of white blood cells and red blood cells.
  • Gram stain: to examine the presence of microbes.

Here are the normal results and possible interpretations:

For physical characteristics:

  • The normal appearance is straw colored, clear or moderately viscous.
  • Less viscous fluid suggests inflammation.
  • Cloudy one indicates the presence of microbes, white blood cells, or crystals, all of which (except a few white blood cells) a normal joint sample should not contain.
  • Reddish one reveals the presence of blood.

For chemical test:

  • Glucose:
    • A normal sample contains glucose, but in a smaller amount than in the blood.
    • So, lower than normal one comes with inflammation and infection.
  • Protein:
    • An increased level suggests bacterial infection.

For microscopic examination:

  • Normally, there are small numbers of white blood cells and red blood cells present in the joint fluid.

For total cell counts:

  • Elevated blood cells numbers occur with infections, and conditions like gout and rheumatoid arthritis.


Keywords: Joint Fluid Analysis; Synovial Fluid Analysis

* The contents of this HTQ Site are for informational and communicational purposes only. The information provided by HTQ, HTQ employees, others appearing on the Site at the invitation of HTQ, or other visitors to the Site is NOT a medical advice.The Content is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read on the HTQ Site!