A bursa is a small, fluid-filled sac that helps tissues glide smoothly over each other. It reduces friction, rubbing, and irritation between muscles, tendons, and bones. The human body contains over a hundred bursae, mostly located near major joints like the hips, knees, shoulders, and elbows. When a bursa becomes inflamed, the condition is known as bursitis. This inflammation can affect many bursae throughout the body and arise from various causes.


