Olecranon bursitis is an inflammatory condition on the back of the elbow. Most patients sense a fluid collection on the bone on the back of the elbow. The condition is common in professional drivers from resting their arm against the car door. It is caused by inflammation producing fluid that accumulates under the skin. Many cases are treated with removal of the fluid and injection of a small amount of corticosteroid to relieve the inflammation. Refractory cases may require removal of the bursa surgically.