This product was authored by Human Kinetics based on the contributions of: Michael C. Koester, MD, ATC, FAAP, is a board-certified sports medicine specialist with more than 20 years of experience in the evaluation and treatment of sports-related injuries and conditions. In addition to being a sports medicine physician, he is a certified athletic trainer and a member of the writing committee for NATA certification exams. He earned his BS in athletic training from the University of Nevada in 1992 and then went on to obtain his MD from the University of Nevada School of Medicine in 1996. A sports medicine fellowship followed at Vanderbilt University, and he most recently became board certified in 2006. His areas of expertise in the active adult population are knee and shoulder injuries.