Rotator cuff disease is the leading cause of shoulder pain and disability. Previous studies regarding the epidemiology of rotator cuff disease have demonstrated a high incidence of age- related cuff tears, approximately 50% of individuals over the age of 55 years 1-3. Failure of conservative treatment often leads to surgical repair of the torn rotator cuff tendons. Indeed, rotator cuff repair is one of the most common surgical procedures currently performed in the shoulder with approximately 200,000 Americans undergoing this surgery yearly. We estimate that the Shoulder and Elbow Service at Washington University performs approximately 400 rotator cuff repairs per year.