[The throwing shoulder].

BACKGROUND: During the throwing motion high forces are placed on the athlete's shoulder and extreme positions of external rotation and abduction are reached. The dynamic and static stabilizers of the glenohumeral joint need to handle a delicate balance between shoulder mobility and stability. CAUSES OF INJURY: Repetitive forces lead to adaptive osseous, capsular, ligament and muscular changes. This should increase external rotation of the shoulder and thus initially help to improve performance but ultimately could cause shoulder pathologies. For instance, tissue overuse can result in muscular imbalance, functional instability and posterior capsular contracture with the development of a glenohumeral internal rotation deficit. INJURY PATTERNS: An internal impingement is often observed in throwing athletes which can be subdivided into the more common posterosuperior type and the rarer anterosuperior type. Typical lesions in the throwing shoulder are articular-sided partial rotator cuff tears, labrum and biceps tendon lesions and edema, cysts or osteochondral lesions of the humeral head or glenoid. DIAGNOSTICS: For an accurate diagnosis it is important to include the history, a thorough physical examination and magnetic resonance arthrography. The correlation of clinical examination and imaging is critical to identify symptomatic lesions. THERAPY: If conservative therapy fails or in cases of significant structural damage resulting in clinical symptoms, surgical treatment should be considered based on the underlying pathology and carried out using established techniques and criteria.