Synoviaalinesteelle

Synoviaalinesteelle, often referred to as synovial fluid, is a viscous fluid found in the cavities of synovial joints. These joints, such as the knee, hip, and shoulder, are freely movable and are characterized by the presence of a joint capsule. The synovial membrane, lining this capsule, secretes the synovial fluid.

The primary function of synovial fluid is to lubricate the joint surfaces, reducing friction between the articular cartilages. This lubrication is crucial for smooth and effortless movement, preventing wear and tear on the bones. The fluid also acts as a shock absorber, distributing pressure evenly across the joint during physical activity. Additionally, it provides essential nutrients to the avascular articular cartilage, which lacks its own blood supply. Synovial fluid plays a role in the immune defense of the joint, containing phagocytic cells that remove debris and pathogens.

The composition of synovial fluid is primarily water, containing hyaluronic acid, proteins, lipids, and cells like leukocytes and fibroblasts. Its viscosity is largely due to the hyaluronic acid component. Under normal conditions, synovial fluid is clear or slightly yellowish and has a gel-like consistency. Changes in the color, clarity, or viscosity of synovial fluid can indicate underlying joint pathology, such as inflammation or infection. Analysis of synovial fluid, known as arthrocentesis, is a diagnostic tool used to identify various joint conditions.