What is Bursitis?
Bursitis (bur-SY-tis) is a painful condition that affects the small, fluid-filled sac — called a bursa, that cushion the bones, tendons and muscles near your joints. Bursitis occurs when a bursa becomes inflamed.
The most common locations for bursitis are in the shoulder, elbow and hip. But you can also have bursitis by your knee, heel and the base of your big toe. Bursitis often occurs near joints that perform frequent repetitive motion.