Anatomic basis of ligamentous control of elevation of the shoulder (reference position of the shoulder joint).

The authors describe in detail the position of greatest stability of the shoulder joint. They review the mechanical importance of this position in the overall physiology of the shoulder-girdle and stress the essential role of two articular ligaments of the shoulder joint (the coracohumeral and inferior glenohumeral ligaments) in arrival at this reference position. There thus exists a passive control, of ligamentous origin, of movements of the shoulder-girdle. The position is essential if the shoulder is to benefit from the full range of movement and full stability which it needs in every day functioning.