Bursae are small fluid-filled sacs located around each joint in the body. Their function is to lubricate the joints and allow them to move freely. The Olecranon bursa is the main bursa of the elbow joint. When injured, usually from a fall or applied force, it becomes inflamed and causes pain throughout the joint. BioSkin Elbow Sleeves are designed to deliver pain-relieving compression to the area, increasing blood flow and speeding recovery.