The location of the starting and ending points of the deltoid muscle is as follows: 1. The starting point of the deltoid muscle is divided into three parts, which are the lateral segment of the clavicle, the acromion and the scapular post. The three positions mentioned above can be positioned in this way. The outer segment end of the clavicle refers to the fact that when the body tilts its head back, there are two horizontal rows of bone on the left and right sides of the chest, which is the clavicle. The lateral part of the clavicle is one of the starting points of the deltoid muscle. The acromion, on the other hand, refers to a very pronounced bony protrusion on the uppermost part of the patient’s outermost shoulder joint, which is the acromion. The scapular post refers to the fact that on the posterior side of the shoulder there is a triangular shaped bone, the scapula. And on its posterior side, there is an oblique, very distinct bony high post called the scapular post. There is a series of muscles attached here, and the deltoid is one of them.2. The stop of the deltoid muscle, placed in the humeral body, is the thick ridge of the deltoid. There is no definite point here, but a longitudinal area. At the lateral part of the proximal humerus, that is, the upper part of the humerus leaning outward, there is a longitudinal area, which is the stop of the deltoid muscle.