There are 4 muscles around the shoulder that control s all the movement of the shoulder. They are very heavy muscles, never tear with minor trauma, it only tears with accident or during sports. Some time due to the ageing process the muscles become thin & weak, so torn with trivial traumaor during regular work. The diagnosis is position, the arm drops like a dead piece which is called drop arm sign. Arthoscopy is the best treatment or solution to get back the arm function, it needs only 2 to 3 holes, and 2 to 3 anchors by which the torn part of the muscles can be pulled back to its original position & implanted to be bone .Needs only 3 weeks rest & then some exercises to get full range of movement & function.