Lesions of the glenoid labrum and their medical-legal interpretation.

Aim: Development of criteria for the medical-legal interpretation of different patterns of labral lesions according to the labrum pathology and mechanism of injury. Methods: A metaanalysis of the literature concerning injuries and diseases of the shoulder involving the glenoid labrum was performed. Results: Lesions of the superior, anterior and posterior labrum are rare and of different severity. Arthroscopically they are divided into distinct types. They develop either spontaneously together with intraarticular diseases, due to chronic fatigue or by injury. In this field the stability of the shoulder joint and the tension of the long head of the biceps tendon play an important role. There is no correlation between the type of lesion and mechanism of injury. With respect to medical-legal interpretation, the currently used classification of labral lesions is not very helpful or is even confusing. We therefore propose a new classification according to the meniscus pathology which shows a striking similarity to labral pathology. There are two types of labral lesions: Type one shows degenerative defects, which may be influenced by mechanical loading; type two follows from shoulder instability. Conclusions: Medical-legal interpretation of labral lesions should follow the same principles that were shown to be useful in knee joint instability and meniscal tears. Only traumatic luxations of the shoulder joint may lead to labral tears without any other alterations.