What is one of the main functions of the synovial membrane?

The synovial membrane is primarily responsible for the lubrication of the joint. It lines the joint capsule and secretes synovial fluid, which acts to reduce friction between the articular cartilage of synovial joints during movement. This lubrication is critical for smooth joint motion and helps to protect the joint surfaces by providing a cushioning effect, thereby facilitating ease of movement and reducing wear and tear on the cartilage.

While the synovial membrane does play a role in protection against infections due to its lining position, lubrication is its primary function. It does not directly provide a blood supply, as the nutrients required for the joint tissues are supplied through the synovial fluid rather than through blood vessels within the synovial membrane. Increasing joint flexibility, while a beneficial outcome of healthy lubrication, is not a direct function of the synovial membrane itself. Therefore, the focus on lubrication highlights the essential role the synovial membrane plays in maintaining joint health and function.