Bursitis is a red, swollen condition of the sac called bursa. Bursae are found in many parts of the body. Usually, muscles and tendons move above the bone. Tendons are solid bands of tissue that connect muscles to bones. Cysts are found on the shoulders, elbows, hips, knees, and feet. The cysts tend to return even after treatment. If the activity that is causing the symptoms is not stopped