Synovial fluid
Synovial fluid ( synovial fluid or even " joint lubricant " ) is a viscous, stringy, clear body fluid in synovial joints. It is formed by the synovial membrane, the inner layer of the joint capsule and forms a lubricating film on the articular surfaces. The term goes back to Paracelsus and is derived from the Greek syn " together with " and Ovia 'protein'.
Composition
Synovial fluid contains :]]
- Hyaluronic acid
- Fat droplets
- 2.5 % protein (1.9% albumin, 0.9% globulin )
- Glucose
- 94 % water
- 0.5 % mucins
- Detached cells of the synovial membrane of the joint capsule and immune cells
Function
The synovium is the nutrition of articular cartilage, lubricate the joint surfaces and contributes together with the articular cartilage for shock absorption in joints with.
The fluid exchange and ensure that the nutrition of articular cartilage is maintained by changing the loading and unloading of the joint cartilage. And a long immobilisation of the joint, but also in case of overload, it comes as a result of eating disorders to cartilage damage.
Other occurrences
Synovial fluid also occurs in sliding means of tendons such as tendon sheaths and bursae.
Abnormal changes
In joint changes, whether it be by an injury, an inflammatory disease or by wear processes, the body responds with increased production of synovial fluid ( Gelenkhydrops ). From the outside, which falls on the swelling of the joint. The palpable mass makes it possible to distinguish between a swelling of the joint capsule and an effusion. If the synovial fluid produced in excess, their composition changes. The normally highly viscous, clear, yellow liquid is watery, sometimes by cell abrasion cloudy or dark colored bleeding ( hemarthrosis = ). Your normal functions it can not perform then, the admixture of blood make the synovial fluid compared to the cartilage even aggressive. In veterinary medicine, which is also referred to as joint bile.
If it remains clear and shows no abnormalities in laboratory findings, one speaks of a reactive effusion. He who comes after injuries, arthritis or after operations on the joint quite often, of course, hinders the function and can stretch the joint capsule. If the effusion is too large, the joint must be punctured. That can happen only under highly sterile conditions, otherwise there is the danger of Gelenkvereiterung Pyarthros. Laboratory analysis of the recovered liquid can provide an indication of the underlying disease. Inflammatory processes, such as rheumatoid arthritis can be detected, as well as disorders of uric acid metabolism in gout.