Tennis elbow, also known as lateral epicondylitis, is an overuse injury that occurs on the outside (posterior) of the elbow. As its name suggests, it commonly occurs in tennis players. However, anyone who consistently uses his elbow or puts the elbow under strain can develop lateral epicondylitis. Tennis elbow occurs when the tendons that attach your forearm muscles to the bone begin to get damaged. Over time, this leads to inflammation and irritation, causing pain on the outside of the elbow.
Tennis elbow symptoms include pain on the outside of the elbow that gradually increases over the course of several weeks or months. In some cases, the onset of pain is immediate, though this is much rarer. The pain may intensify when squeezing or gripping objects, lifting, or using utensils and tools. Other symptoms include weakness and stiffness.