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:
- A normal sample contains glucose, but in a smaller amount than in the blood.
- So, lower than normal one comes with inflammation and infection.
- 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