Elbow bursitis causes fluid to collect in a sac that lies behind the elbow, called the olecranon bursa. A bursa is a slippery, sac-like tissue that normally allows smooth movement around bony protrusions, such as the point behind the elbow. When a bursa becomes inflamed, the sac fills with fluid. This can cause pain and swelling behind the elbow.
Elbow bursitis may follow a traumatic accident, such as the result of a fall or it may appear out of nowhere. People who rest their elbows on hard surfaces may aggravate the condition and make the swelling more prominent.Occasionally, the swelling and inflammation to the elbow can be the result of an infection within the bursa. This is called infected elbow bursitis. Patients with systemic inflammatory conditions, such as gout and rheumatoid arthritis, are also at increased risk of developing infected elbow bursitis.