Most shoulder problems involve the soft tissues-muscles, ligaments, and tendons-rather than bones.
Most of these problems fall into these major categories:
Rotator cuff injuries are among the most common of these disorders. The rotator cuff is the arrangement of muscles and their tendons, which provides shoulder motion and stability.
Sometimes, excessive use of the shoulder leads to inflammation and swelling of a bursa, a condition known as bursitis. Bursas are fluid filled sacs located around the joint that lessen the friction caused by movement of the shoulder. Bursitis often occurs in with rotator cuff tendonitis. Sometimes the many tissues in the shoulder become inflamed and painful, limiting the use of the shoulder. The joint may stiffen as a result, a condition called a "frozen shoulder." Fortunately, with appropriate care, this condition will resolve
Shoulder pain can also result from arthritis. There are many types of arthritis, but generally it involves wear and tear changes with inflammation of the joint, causing swelling, pain, and stiffness. Arthritis may be related to sports or work injuries.