What can cause pain beneath the elbow?

Bursitis: Pain in the back of the elbow is considered the posterior elbow. More commonly there is a bursal sac between the skin and the bone. It can become inflamed and cause bursitis. This can either be traumatic when you hit the back of your elbow or a traumatic from inflammation. Typically it will swell back there. Usual treatment is anti-inflammatories like ibuprofen and a compressive ace wrap.