Jeffrey N. Katz, MD, MSc, Cheri Blauwet, MD, and Andrew Schoenfeld, MD, MSc are all part of the Department of Orthopedic Surgery, Brigham and Women’s Hospital and Harvard Medical School. Chapters will be written by members of their department. Dr. Katz is a Professor of Medicine, Orthopedic Surgery, Epidemiology, and Environmental Health at Harvard and holds a number of leadership positions, including Director, Orthopaedic and Arthritis Center for Outcomes Research at Brigham and Women’s Hospital.Dr. Blauwet is an Instructor of Physical Medicine and Rehabilitation at Harvard.Dr. Schoenfeld is an Assistant Professor of Orthopedic Surgery at Harvard.