Disturbances in the region of insertion or point of attachment of ligaments or tendons to the bones (known as "enthesopathy") comprise, besides endocrinological and metabolic diseases, mainly traumatic, inflammatory and degenerative changes. The two imaging methods that are most suitable for investigating the soft parts are sonography and magnetic resonance tomography. Sonography has become the most widely used diagnostic tool for tendon lesions in sports due to its ability to analyse muscles and ligaments in any desired projection and functional state on a "real time" basis. Within just one year (1987) we examined sonographically 86 sportsmen clinically suspected of lesions of tendons and paid particular attention to documentation of sonomorphological changes of the tendons and peritendonous soft parts, as well as to the objectivation of treatment effects in follow-ups. Advantages of real time sonography in anomalies of tendons are: 1. confirmation of rupture if clinical signs and symptoms are vague; 2. differentiation between intratendinous and peritendinous structural changes; 3. diagnosis and follow-up control in lesions of the apophysis in adolescents without risk of irradiation exposure; 4. non-invasive follow-ups and objectivation of treatment effects in conservative and surgical treatment; 5. diagnostic on-target sonographically controlled aspiration of synovial fluid; 6. dynamic assessment of function of tendon play under real time conditions. Hence, sonography of the soft parts should be used as the method of choice to clarify any lesions of tendons and ligaments, since it is an easily appreciated, readily available, low-cost and sensitive imaging method.