You don't have to be a tennis player to get tennis elbow. It’s when the tendons in the elbow become swollen. This swelling occurs when you overuse the tendons while doing activities that require repeating the same motion over and over. Although not as common, a direct blow to the elbow can also raise your chance of getting tennis elbow. Your elbow is where your humerus, the large bone in your upper arm, meets the radius and ulna, the 2 bones in your lower arm, or forearm. On either side and slightly in front of the point of your elbow, there are 2 bumps called lateral epicondyles. The medical term for tennis elbow is lateral epicondylitis.