Rotator cuff (RC) tears refer to a partial or full discontinuation of one or more of the muscles or tendons and may occur as a result of traumatic injury or degeneration over a period of years. The incidence of RC tears is related to increasing age; 54 percent of patients over the age of 60 years have partial or complete RC tears compared with only 4 percent of adults under 40 years of age. Although not a life-threatening condition, RC tears cause significant pain, weakness, and limitation of motion. Both non-operative and operative treatments are used in an attempt to relieve pain and restore movement and function of the shoulder. This book examines the comparative effectiveness of the various non-operative and operative treatment options for patients with RC tears.