The shoulder joint also known as the glenohumeral joint, is the major joint of the shoulder, but can more broadly include the acromioclavicular joint. In human anatomy, the shoulder joint comprises the part of the body where the humerus attaches to the scapula, the head sitting in the glenoid cavity.he joints of the shoulder are the shoulder joint (or glenohumeral joint), and the acromioclavicular joint. Another joint in the shoulder is the sternoclavicular joint that articulates with the sternum and clavicle.