At the root of Tennis elbow, or "lateral epicondylitis" is similar culprit responsible, as is in most tendonitis situations, and that is worn out tendons. The repetitive stress placed on elbow tendons carrying out a similar strained elbow motion above and above, ends in micro tears around the tendons that connect the forearm muscle groups for the arm bone connecting on the elbow joint. The result from such don is unbearably and pretty constant suffering.