Elbow Bursitis occur for several reasons:
Trauma: A hard hit on the top of your elbow can result in the bursa producing excess fluid and swell.
Prolonged Pressure: Leaning on the elbow over a long period of time on a hard surface may cause the bursa to swell. This type of bursa will develop over several months. Hard surfaces like table tops or hard floors make certain professions more vulnerable to these types of bursas
Infections: An injury on the elbow that breaks the skin can get in and infect the bursa. An infected bursa can produce fluid, redness, swelling, and pain.
Medical Conditions: Certain medical conditions such as rheumatoid arthritis and gout have been associated with elbow bursitis