History typically reveals a fall on an outstretched hand.  Physical exam reveals diffuse tenderness and swelling with bony posterior elbow prominence.  The brachial artery and median nerve are at risk for injury with posterior dislocations and should be assessed before and after reduction attempts.

     For anterior dislocations, the mechanism is a direct blow to the olecranon with the elbow flexed.  Physical exam reveals a shortened upper arm and elongated forearm with the elbow held in full extension.  Perform a careful vascular exam.