A drawback of traveling is carrying your suitcase everywhere, particularly lifting it into overhead compartments on planes, trains and buses. This really hurts my shoulder. Apparently, I am straining my rotator cuff muscles and tendons. As we age, these soft tissues surrounding the shoulder tend to weaken and are easily injured.
Here is short summary on Rotator Cuff Disease, published in Aches & Joints.
Primary Cause of Shoulder Pain and Treatment Options.
There are several causes of shoulder pain. In the elderly, shoulder pain is commonly associated with aging and can be traced to rotator cuff disease. In younger people, it is associated with throwing or overhead sporting activities that result in injury to the rotator cuff.
The rotator cuff is a band of four muscles and tendons at the shoulder joint, which grasp the end of the upper arm or humerus (HYU-mer-us, see figure), much like four fingers holding a baseball. The rotator cuff thus stabilizes the shoulder joint and provides exceptional mobility to the arm. Pinching, irritation, or tears of the rotator cuff are common causes of shoulder pain.