Proximal humerus fracture (fractured shoulder)
The shoulder is made up of three bones, the clavicle (collarbone), the scapula (shoulder blade) and the humerus (upper arm bone). The upper part of the humerus is called the proximal part of the bone. Many muscles surround your shoulder. These include the rotator cuff muscles, deltoid muscle, pectoral muscles and several strong back muscles. The arteries and nerves that supply your arm come out from under your collarbone and travel down your arm in front of your shoulder.