Bursae are small, fluid-filled sacs that occur in various parts of the human body. They are found near joints where friction might occur between bones, tendons, or muscles. These sacs act as cushions or shock absorbers, reducing friction and enabling smooth movement.
The structure of a bursa consists of a thin, fluid-filled sac that is lined with synovial cells. These cells secrete synovial fluid, which is a lubricating substance that helps reduce friction during movement. Bursae can vary in size and shape, depending on their location and function within the body.
Bursae are primarily responsible for preventing or reducing excessive rubbing and friction between adjacent tissues. This protective mechanism enhances joint mobility and reduces the risk of injury or irritation. Inflammation of a bursa is known as bursitis, which can occur due to repetitive movements, prolonged pressure, or infection.
Some common areas where bursae are found include the shoulder, elbow, hip, knee, and Achilles tendon. For instance, the subacromial bursa found in the shoulder helps reduce friction between the rotator cuff tendons and the acromion process of the scapula, allowing smooth shoulder movement.
Overall, bursae play a crucial role in supporting joint function by reducing friction and preventing damage to adjacent tissues. Their presence ensures optimal movement and protects the body from excessive wear and tear.
