Definition
An inflammation of the synovial membrane, also called synovitis, is an inflammation of the inner lining of a joint, the membrana synovialis. The membrana synovialis produces synovial fluid, which acts as a shock absorber in the joint and supplies the joint cartilage with nutrients. During an inflammation, which can be acute or chronic, the membrana synovialis can proliferate into the joint space and into the joint cartilage and destroy it. More synovial fluid is produced and inflammatory cells of the immune system are activated and migrate. In the case of severe inflammation, ligaments or tendons can be injured and the entire joint destroyed.
Causes
Inflammation of the joint mucosa can occur for various reasons. Bacterial or viral infections and the body’s reaction to the foreign bodies can lead to a severe inflammation of the joint space. Permanent over-irritation of the joint, for example in athletes, or constant pressure or impact stress with the same sequence of movements at work also increase the risk of inflammation.
Due to age-related wear and tear of the joints, which can be accompanied by degenerative diseases such as arthrosis, synovialitis is not uncommon. In severe arthrosis in the joint, in which the cartilage is destroyed, rubbing of the joint surfaces and detached cartilage particles can lead to inflammation of the joint mucosa. Severe violent impacts or trauma of a joint can also lead to inflammatory processes.
Synovitis can be caused by autoimmune diseases in which the body mistakenly defends itself against the body’s own substances. Examples of autoimmune diseases that can lead to inflammation of the synovial membrane are rheumatoid arthritis or psoriatic arthritis. Metabolic diseases, such as gout, where there is too much uric acid in the body, can also cause inflammation in various joints.
In this metabolic disease, crystals form in the joint due to the excess uric acid, which activates the immune system and leads to a defensive reaction and inflammation. Allergic reactions can also be causes of synovitis. Osteoarthritis is a degenerative joint disease that is associated with joint wear and tear.
Increasing age-related cartilage abrasion occurs. Rubbing of the joint surfaces and detached cartilage particles in the joint space can lead to irritation of the joint mucosa and thus to synovitis. The proliferation of the membrana synovialis and the resulting increased production of synovial fluid is responsible for the resulting joint effusion.
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