Crystals Associated With Osteoarthritis
There is a connection between osteoarthritis and crystal pyrophosphate dihydrate (CPPD) deposition that is considered significant. About 70% of CPPD cases are associated with chronic arthritis that is very similar to osteoarthritis of the hips, wrists, and knees.
Basic calcium phosphate crystals (BCP) are also commonly found in the joint fluid and tissues of osteoarthritis patients. And then, there was the possible connection between hydroxyapatite crystals and osteoarthritis described by researchers in 1976.
The Significance of Crystals
It is still unknown why the crystals form. Their role, if any, in causing joint damage in osteoarthritis also remains unexplained. First of all, for years osteoarthritis was thought of as a non-inflammatory type of arthritis. Over time, researchers have found that inflammation does play a role in osteoarthritis. The current thinking is that inflammation is not merely present -- at some level, it is related to the cause of the disease.
Initial research indicates that there are calcium-containing crystals in the tissues of nearly all patients who have end-stage osteoarthritis. The inflammatory properties of calcium-containing crystals may bring about the damaging effects in osteoarthritis through innate immunity signals. The innate immune system is one of the two branches of our immune system. The other is called the adaptive immune system.
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Innate immune system activation in osteoarthritis: is osteoarthritis a chronic wound? Scanzello CR et al. Current Opinion in Rheumatology. Sept 2008. Vol 20 Issue 5 Pages 565-572. http://www.ncbi.nlm.nih.gov/pubmed/18698179
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