Tennis elbow’ (Lateral epicondylitis) is caused by a physical strain. Of course, a strenuous game of tennis can be the cause, but it can also be caused by any one of a number of activities. People who are continually gripping and twisting – carpenters and plasterers, for instance – are particularly prone to this painful condition.
T. The lateral epicondyle is the bony part you can feel on the outside of your elbow joint. It is outside the joint and so is unaffected by arthritis or deformity, but it is often prominent, especially in thinner people, and consequently it can easily be knocked, which causes soreness and bruising.
Tennis elbow usually arises when the tendons coming from the muscle of the forearm become inflamed at the point where they join the epicondyle.