If one uses the expression "tennis elbow", almost everybody knows which pains are meant. From a medical point of view it is about a pain syndrome whose origins are located in the area of the hands` and also fingers` musculature and at the outer insertions of the upper arm bone (humerus). Therefore a so-called inflammation of the tendons` insertion (=tendonitis of the insertion), at which mainly the stretching musculature of the forearm is concerned, is meant by a tennis elbow. The inflammation is usually caused by an overstraining during the occupation or also during sports (e.g. tennis). This explains the origin of the name "tennis elbow".