The Elbow is a hinge joint made up of the arm (humerus) and the forearm (ulna and radius). This joint allows for rotation as well as hinge action.

The most common injury to the elbow is the Tennis Elbow (Lateral Epicondylitis)

This can develop in anyone who uses the arm for heavy activities, or sudden injury to the arm.
The cause for Tennis Elbow (Lateral Epicondilitis) is thought to be partial tearing of the extensor muscles.
Treatment is by immobilization and injection of anti-inflammatory drugs to the point of injury. surgical release is rarely undertaken.