Osteoarthritis (OA), also known as degenerative joint disease, is the most common form of arthritis. This disease is characterized by gradual loss of the cartilage that cushions and protects the bones, abnormal bone growth around the joint, and other joint changes that cause pain and disability. According to the Arthritis Foundation, OA affects 27 million individuals in the United States alone, most aged > 45 years. This disorder affects women more than men; however, it is still one of the five leading causes of physical disability, morbidity, and social isolation in noninstitutionalized older men and women. After knee and hip OA, the shoulder is the most common site of OA occurrence. Rheumatoid arthritis (RA) can also damage the shoulder as a result of an immune system attack on the tissue lining the shoulder joint. Patients who have severe joint damage that does not respond adequately to medication and other conservative therapies may require surgical repair.