Arthritis
Shoulder pain can result from arthritis. The most common type of arthritis in the shoulder is osteoarthritis, or wear and tear arthritis. Osteoarthritis develops slowly, eventually causing swelling, stiffness, and pain. Other types of arthritis can be related to joint lining inflammation, rotator cuff tears, or infection. Symptoms include pain aggravated by activity, limited range of motion, a grating sensation (crepitus), weakness, and difficulty sleeping.
Dislocations 
