The shoulder is sometimes subject to dislocation, but as for the scapula, the possibility of its dislocation is doubtful, and the fact that it is dislocated is considered unusual. But the shoulder joint of the shoulder bone sometimes dislocates easily, because its fossa is shallow and the ligaments are not strong, but soft and thin, made so as to facilitate movement.
Dislocation of this joint with a clear, significant deviation occurs, as far as we know, only in one direction it does not dislocate, neither upward, because the protrusion of the shoulder prevents this, nor backward, since the scapula prevents this, nor towards the abdomen, because the muscle with two heads in front prevents this if there is an obstacle also from the side of the humeral head. When dislocating internally or externally, the joint moves only slightly in this direction, whereas when dislocating in a downward direction, it sometimes moves significantly, especially in skinny, thin people. In such people, dislocation of the humerus and its reduction occur from the most insignificant reasons, but in obese people both of these actions are very difficult. When a dislocation of the humerus occurs, as you know, during a difficult birth or during the cutting out of a fetus and it is not quickly set, then the bone does not grow in length after that and the elbow remains thin, even if the joint is later corrected. Sometimes in some people it does not thicken and remains short and thin, with a thin humerus and forearm, and in many the humerus thickens and is often in good condition, but in any case it is short, similar to the front leg of a weasel. As for the hip, after dislocation it is not free from both of these defects. If a transverse fracture occurs in the humerus and it is fused, then it is absolutely impossible to set the dislocation without breaking the fusion.