What are bursae?

Bursae are small, fluid-filled sacs located in joints throughout the body. They act as cushions to reduce friction between tissues, such as bones, tendons, and muscles, during movement. This function is particularly important in areas where there is a lot of motion, as bursae help to facilitate smooth movement and reduce wear on the surrounding structures. By providing lubrication, they play a crucial role in joint health and mobility, which is vital for many physical activities.

The other options describe different anatomical structures. Muscles, ligaments, and tendons are essential components in movement and stability but do not serve the specific function of cushioning joints like bursae do. Understanding the role of bursae in joint function can aid in recognizing conditions like bursitis, which involves inflammation of these sacs and can significantly impact movement and comfort.