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Our Board

Tom Denninger, DPT, OCS, FAAOMPT and ATI Vice President of Clinical Development

Executive Director

Tom Denninger serves as Vice President for Clinical Development ATI Physical Therapy, where he oversees all internal and external clinical education and development programs. Mr. Denninger has been with ATI since 2015 working in a variety of patient-facing, operational, and corporate roles. He completed his Doctorate of Physical Therapy and Orthopedic Residency at Sacred Heart University in Fairfield, CT and completed his fellowship in manual physical therapy through Evidence in Motion. Mr. Denninger has presented at national conferences and has multiple peer-reviewed articles.

Dr. Ellen Shanley, PhD, PT, OCS and ATI Senior Director of Care Delivery Optimization

Vice President

Dr. Ellen Shanley, PhD, PT, OCS, is a clinical research scientist and serves as Senior Director of Care Delivery Optimization at ATI Physical Therapy.  Formerly, she served as the Director of Athletic Injury Research, Prevention, and Education for the South Carolina Center for Rehabilitation and Reconstruction Sciences as well as sat on the faculty at the University of South Carolina in the School of Public Health, Clemson University School of Bioengineering and Rocky Mountain University of Health Professions PhD program. She is a co-founder of the APTA credentialed Upper Extremity Fellowship for ATI and the following professional teams: Kansas City Royals™, Colorado Rockies™, and Chicago Cubs™. She has previously and continues to mentor residents, fellows and PhD students.

Dr. Shanley specializes in the treatment of patients with upper extremity injuries. As a member of the American Society of Shoulder and Elbow Therapists (ASSET), Shanley has served as the Education Chair and the Society’s President-Elect. Dr. Shanley has been awarded the APTA’s Excellence in Research Award, ASSET’s Founders Award and was the first physical therapist to be invited into the American Shoulder and Elbow Surgeons (ASES) Neer Circle.

Dr. Adam Lutz, PhD, PT, DPT, MBA and ATI Director of Care Quality and Innovation


Dr. Adam Lutz serves as Director of Care Quality and Innovation for ATI and holds the position of Secretary on the board of iMSKA. His academic journey began with a Bachelor of Science in Kinesiology and Human Movement Science from Louisiana State University, followed by a Doctor of Physical Therapy from the University of North Florida. Dr. Lutz was a Presidential Fellow during his PhD studies at the University of South Carolina and expanded his expertise with an MBA, concentrating on Finance, from Louisiana State University – Shreveport. His diverse clinical background includes roles within ATI Physical Therapy and as a contract physical therapist for the U.S. Navy, where he gained a valuable understanding of direct access physical therapy and physical therapy as a primary care provider for musculoskeletal conditions.

Dr. Lutz’s approach is data-driven and outcome-focused, utilizing his analytical skills to dissect and understand healthcare databases, thereby enhancing the efficacy and efficiency of clinical pathways. His zeal for collaboration positions him well to work closely with universities and bridge the gap between academia and clinical practice. Dr. Lutz is deeply committed to leading and advancing ATI’s research agenda, ensuring it aligns with its mission to deliver top-tier musculoskeletal care at a value to the healthcare ecosystem. His balanced view of patient care, business strategy, and research innovation makes him a champion of integrating cost-effective care, clinical excellence, and a superior healthcare experience for both providers and patients. Dr. Lutz’s methodology is characterized by pragmatism in solving real-world healthcare problems, which is crucial for navigating the complexities of today’s healthcare landscape.

Augustus Oakes, ATI Chief Information Officer


Augustus Oakes leads technology for ATI Physical Therapy and serves on the executive leadership team. Prior to joining ATI in 2018, Mr. Oakes served as a management consultant at KPMG LLP where he helped companies build modern IT operating models and prepare for digital disruption. He also served in various IT leadership roles at Walgreen Company and as a management consultant with Accenture. Mr. Oakes holds a degree from Loyola University Chicago.

Our Advisory Board

Michael Kissenberth, MD

Dr. Kissenberth specializes in sports medicine, arthroscopy and complex reconstruction of the shoulder, elbow and knee. He also has expertise in shoulder replacement surgery. He is a national expert in the care of the throwing athlete, particularly the young thrower. Dr. Kissenberth has published many peer-reviewed articles and book chapters, and he lectures nationally. He is a physician advisor for ongoing research evaluating the risk factors, treatment strategies and critical steps for return to sport in throwing athletes. He serves as a consultant to the Colorado Rockies Baseball Club and is vice chair of Clinical Affairs of the GHS Department of Orthopaedics. Dr. Kissenberth is a graduate of The Citadel, where he captained the football team, and attended the Medical University of South Carolina. He completed his residency in Orthopaedic Surgery at Tripler Army Medical Center and served his fellowship in Sports Medicine with Steadman Hawkins Clinic of the Carolinas and the Hughston Clinic in Columbus, Georgia.

Jennifer Stevens-Lapsley, PT, PhD, FAPTA

Dr. Stevens-Lapsley is a Professor and Director of the Rehabilitation Science PhD Program as well as the PT Section Director for Research and Development in the Physical Therapy Program at the University of Colorado Anschutz Medical Center. She is also the Associate Director for Research for the Geriatric Research Education and Clinical Center within the Eastern Colorado VA Healthcare System. She is focused on identifying, integrating, and advancing innovative evidence-based medicine solutions for older adult rehabilitation through highly effective research methods and partnerships. She has 20 years of clinical research experience including patients after joint arthroplasty and medically complex patient populations. Her clinical research has resulted in over 175 publications, numerous awards, and over $20 million dollars to support her clinical research in the past 15 years.

Trevor Lentz, PT, PhD, MPH

Dr. Lentz is an Assistant Professor in Orthopaedic Surgery at Duke University, with appointments in the Musculoskeletal and Surgical Sciences (MASS) therapeutic area at the Duke Clinical Research Institute (DCRI), the Duke-Margolis Institute for Health Policy, and the Duke Surgical Center for Outcomes Research and Equity in Surgery (SCORES). Trained as a physical therapist and health services researcher, his research focuses on developing tools and processes that facilitate whole person care in populations with musculoskeletal pain and orthopedic injury. He have extensive experience in the development, psychometric assessment, and implementation of psychological and mental health assessment tools in populations with musculoskeletal pain (i.e., the OSPRO Yellow Flag and Screening for Pain Vulnerability and Resilience (SPARE) Assessment Tools).

Lori Michener, PhD, PT, ATC, SCS, FAPTA

Lori Michener, PT, ATC, PhD, FAPTA is a Professor, Director of Clinical Outcomes and Research, and Director of the COOR Laboratory in the Division of Biokinesiology and Physical Therapy at the University of Southern California in Los Angeles CA in the United States. She is a Board Certified Clinical Specialist in Sports Physical Therapy (SCS) and see patients at USC’s clinical practice. She earned degrees in Athletic Training and Physical Therapy, and her PhD in Orthopedics and Biomechanics from MCP Hahnemann University in Philadelphia, Pennsylvania. The central theme of COOR lab’s funded research is to define optimal treatment pathways for patients with musculoskeletal shoulder disorders by characterizing biomechanical and central (brain) mechanisms related to the presence of movement deficits and poor recovery, defining classification and management approaches, and determining optimal outcomes of care. COOR Lab:

Kate Minick, PT, DPT, PhD

Kate Minick is the Director of Research & Quality for Rehabilitation Services and an Assistant Professor of Clinical Research at Intermountain Healthcare. Her research is focused on the implementation of best practices, improving patient-reported outcomes, and identifying the value of physical therapy in a changing healthcare environment. She has over 15 years of clinical research experience, including large multi-disciplinary pragmatic trials, embedded research, hybrid-implementation trials, and quality improvement

Amit Momaya, MD

Dr. Amit Momaya is a sports medicine surgeon and serves as head of the sports medicine division within the Department of Orthopedic Surgery at the University of Alabama at Birmingham. He has extensive experience in the care of patients with shoulder, elbow and knee injuries. Furthermore, he has taken care of athletes at all levels—from the weekend warrior to the professional athlete. Dr. Momaya currently serves as team physician for UAB Athletics, Birmingham Legion FC, Birmingham Bulls Hockey, BUSA soccer, Hoover Vestavia Soccer, and multiple high schools. In addition, Dr. Momaya is an active clinician scientist. His research has been published in leading Orthopedic journals and presented at multiple local and national meetings. He continues to engage in clinical trials to help improve patient care and innovate in the growing field of sports medicine.

Dr. Momaya was born in Chicago, IL, but spent most of his formative years in Atlanta, GA. He grew up playing multiple sports including baseball and was an avid long-distance runner. He earned his undergraduate degree in biomedical engineering at Duke University. He received his medical degree from the Baylor College of Medicine in Houston, TX. He was then matched into a competitive orthopedic residency at the University of Alabama at Birmingham. He also received training at the Andrews Sports Medicine Institute taking care of high-level athletes. He then decided to dedicate an extra year to hone his skills within sports medicine and secured a fellowship at the nationally renowned Steadman Hawkins Clinic. After fellowship, Dr. Momaya joined as faculty at the University of Alabama at Birmingham.

Mark V. Paterno, PT, PhD, MBA, SCS, ATC   

Mark V. Paterno PT, PhD, MBA, SCS, ATC is a physical therapist, clinical scientist and Senior Clinical Director within the Division of Occupational Therapy and Physical Therapy at Cincinnati Children’s Hospital Medical Center in Cincinnati, OH. Mark also serves as a Professor within the Division of Sports Medicine at Cincinnati Children’s Hospital.  In addition to his administrative role, leading the Division of Occupational Therapy and Physical Therapy, Mark supports an active research program focused on outcomes after lower extremity musculoskeletal injuries in children, adolescents, and young adults.  This work has led to over 100 publications and 12 book chapters which focus on the area of outcomes after ACL reconstruction and pediatric sports medicine. He currently serves as research committee chair for the American Academy of Sports Physical Therapy (AAPST), a founding member and Past President for the Pediatric and Adolescent Research in Sports Medicine (PRISM) Society as well as a founding member of the ROCK group, which is an international, multi-disciplinary group, dedicated to researching juvenile osteochondritis dissecans.

Laura Pietrosimone PT, DPT, PhD

Laura Pietrosimone completed her Bachelor of Science in Psychology at Duke University in 2006, Doctor of Physical Therapy (DPT) degree at Duke University in 2010, followed by the Proaxis Therapy post-professional sports residency program, and received her PhD in Human Movement Science at the University of North Carolina at Chapel Hill in 2018.  Her research focuses on developing biopsychosocial interventions to address the lasting physical and psychological consequences of both acute and chronic lower extremity injuries. She is particularly interested in exploring how both laboratory biomechanics measurement and real-world physical activity assessments intersect and developing innovative, personalized rehabilitation strategies to promote movement and optimize patient quality of life. Her work is primarily focused on athletic and active populations who experience sports-related traumatic injury and chronic overuse injury, particularly ACL injury and lower extremity tendinopathy, respectively, but she is passionate about inter-disciplinary initiatives that promote wellness and physical activity across many populations with musculoskeletal conditions. In particular, she works closely with the Division of Sports Medicine and the interdisciplinary team at the Duke Sports Science Institute and with the Michael W. Krzyzewski Human Performance Lab (K-Lab) to drive patient-centered clinical research in orthopedics and sports medicine.

Amee L. Seitz, PT, DPT, PhD

Amee L. Seitz, PT, DPT, PhD is an Associate Professor in the Department of Physical Therapy and Human Movement Sciences at the Feinberg School of Medicine, Northwestern University. Dr. Seitz’s research seeks to optimize treatment outcomes, health, and performance for individuals with musculoskeletal disorders. She directs the Musculoskeletal Biomotion Laboratory on Northwestern Medicine Chicago campus with collaborations in Orthopaedics, Bioengineering, and Emergency Medicine that focuses on clarify underlying neuromuscular mechanisms, structure, and function associated with shoulder injury, diagnosis, and rehabilitation management. Dr. Seitz is an active contributor to Clinical Practice Guidelines for a variety of shoulder disorders and engaged in research facilitating best care practices including early physical therapist management of patients with musculoskeletal pain. She is currently Research Chair for the Academy of Orthopaedic Physical Therapy and former President of the American Society of Shoulder and Elbow Therapists.

Chuck Thigpen, PhD, PT, ATC

Dr. Thigpen is Senior Vice President for Clinical Excellence for ATI Physical Therapy leading the clinical services and quality improvement across the ATI platform to prevent and treat of musculoskeletal disorders. Dr. Thigpen holds adjunct appointments with Duke University Department of Orthopaedics, Division of Physical Therapy, University of South Carolina Department of Physical Therapy, and Clemson University Bioengineering. Chuck completed his PhD in Human Movement Science from the University of North Carolina-Chapel Hill in 2006. He completed a M.S. in Human Movement Science with a concentration in Orthopedic and Sports Physical Therapy from UNC in May of 2003. He earned his B.S. in Physical Therapy from East Tennessee State University in 1997. Chuck played football at the University of Tennessee-Chattanooga in 1991-92 before becoming a student athletic trainer through 1995.

Today he leads the clinical services and care innovation aimed to deliver predictable outcomes while bending the cost curve for patients with MSK related pain. He leads the clinical quality improvement and benchmarking for ATI’s Patient Outcomes Registry, the largest in physical therapy with over 3.3 million individual patient episodes. He has been funded by the MIT research endeavor (MITRE) and Foundation for Physical Therapy for health innovation in development of clinical pathways for orthopaedic related pain. He has over 100 peer-reviewed scientific papers published in leading scientific journals including Journal of Bone and Joint Surgery, American Journal of Sports Medicine, Journal of Shoulder and Elbow Surgery, Journal of Orthopedic and Sports Physical Therapy, and British Journal of Sports Medicine and his work has been cited more than 1000 times.

Thigpen is a NATABOC certified athletic trainer and a member of the National Athletic Trainer’s Association, American Academy of Orthopaedics and Sports Physical Therapy, American Shoulder and Elbow Society, American Society of Shoulder and Elbow Surgeons, and The ICCUS Society for Sports Rehabilitation. He served as the research chair for the American Academy of Sports Physical Therapy from 2012-2018 and as President of the American Society of Shoulder and Elbow Therapists from 2010-12. Dr. Thigpen received the 2008 Founders award for service to the American Society of Shoulder and Elbow Therapists. In 2012, he was awarded the APTA Academy of Sports PT “Lynn Wallace Award for Clinical Education and Mentoring” in recognition of his contributions to sports physical therapy in the areas of teaching and mentoring and in 2022 the “Clinical Excellence Award” for career contributions to sports PT research. In 2015, Thigpen was inducted as an inaugural member of the East Tennessee State University’s College of Clinical and Rehabilitative Health Sciences Alumni Hall of Fame.

John Tokish, MD

Dr. Tokish is a 1991 USAF Academy graduate where he was an Academic All-American and All Conference Linebacker in 1990. He graduated medical school from the University of Washington, Seattle and completed residency at the University of Arizona. He was elected to AOA during his medical education and completed an Orthopaedic Sports Medicine fellowship at the Steadman Hawkins Clinic in Vail Colorado in 2001. He returned to the Air Force Academy and served as head team physician and chief of sports medicine from 2001-2009. He spent one year at Luke AFB, Arizona where he was an Assistant Team Physician for the Phoenix Coyotes. In 2010, he was transferred to Honolulu, HI, where he was appointed Residency Program Director at Tripler Army Medical Center. He separated from the military in 2014, and joined the Steadman Hawkins Clinic of the Carolinas. He currently serves as Associate Chair of Research and Director of the Orthopedic Sports Medicine Fellowship at Mayo Clinic Arizona.

Dr. Tokish has authored over 75 peer reviewed publications and book chapters, and is the editor of two books. He has received funding from the OREF, NIH, and US government granting agencies. He established the military’s first orthopaedic sports medicine outcomes database, and has established the first sports medicine QCDR in the US. His work has been awarded the Hughston award by the American Journal of Sports Medicine in 2016, as well as the AirCast Award for basic science and the The American Orthopaedic Society for Sports Medicine Fellow Research Award in Clinical Science. Dr. Tokish served as President of the Society of Military Orthopaedic Surgeons in 2010, and was founder of the SOMOS research collaborative. He served two tours of duty in support of the Global War on Terror. He currently serves on the Board of Directors of the Hawkins Foundation, CEROrtho, Orthopaedics Today, and the Arthroscopy Association of North America (AANA). He has given over 200 national and international podium presentations, and has founded or chaired more than 15 national Orthopaedic Meetings.

Craig Wassinger PT, PhD

Craig Wassinger PT, PhD is a Professor and the Director of Research in the Doctor of Physical Therapy program at the Tufts University School of Medicine in Boston. Craig received his physical therapy degree from Daemen College. He completed his master’s degree in orthopedic manual physical therapy and PhD in sports medicine, both from the University of Pittsburgh. He also completed a post-doctoral research fellowship focusing on pain science at the University of Otago in New Zealand. Craig has a clinical specialization as a therapeutic pain specialist. He has authored numerous peer-reviewed and scientific publications and presentations with research foci on musculoskeletal shoulder pain, psychosocial contribution to physical therapy practice, and the scholarship of teaching and learning. He has also served in many professional service roles including practice committee chairperson of the Pain Special Interest Group of the American Physical Therapy Association, clinical practice guideline developer for the Academy of Orthopaedic Physical Therapy, and executive board member of the American Society of Shoulder and Elbow Therapists. He is an editorial board member for the journals Physiotherapy Practice and Research and Physical Therapy Reviews.  Clinically, Craig mentors orthopedic residents and manual therapy fellows in the areas of pain science, psychosocial aspects of practice, and evidence-based practice.

Research Partners

John Brooks, PhD

Dr. Brooks a health economist with a focus on estimating treatment effectiveness using observational healthcare databases. He has a Ph.D. in economics from the University of Michigan. Dr. Brooks was a Service Fellow at the Agency for Healthcare Research and Quality and a Professor at the University of Iowa Colleges of Pharmacy and Public Health prior to coming to the University of South Carolina. He is the Director of Center for Effectiveness Research in Orthopaedics (CERortho) which is a collaborative effort between the University of South Carolina and Prisma Health to promote comparative effectiveness research (CER) in orthopaedic care. CERortho enables methodologists and clinicians in a large dynamic healthcare system to create prospective data collection platforms and develop innovative methods in treatment effectiveness research. The CERortho strategy is to develop repositories containing patients with MSK conditions and measuring information from throughout their episodes of care to assess treatment effectiveness. The Orthopaedic Patient Data Repository follows populations of patients from Prisma Health with new musculoskeletal (MSK) conditions through their entire episodes of care.

Garrett Bullock, PT, DPT, DPhil

Dr. Garrett Bullock is a former professional baseball player, physical therapist, and quantitative epidemiologist. Dr. Bullock was a Clarendon Scholar at the University of Oxford prior to joining the faculty at Wake Forest School of Medicine. Dr. Bullock also holds an honorary appointment with the United Kingdom Centre for Sport, Exercise, and Osteoarthritis Research Versus Arthritis. Dr. Bullock’s research focus is in creating real-world clinically applicable research, that has direct application in orthopaedic and sports medicine. Dr. Bullock’s specific research entails risk and risk mitigation, life span impact of exercise and sport, and the influence of clinical decisions on patient care. Dr. Bullock has received multiple federal and private organization grants, and has worked with multiple national and international professional athlete organizations and leagues through both consulting and academic projects.

Chad Cook, PT, PhD, MBA, FAPTA

Dr. Cook is a health economics researcher (PhD) with formal post-graduate training in chronic pain management. He has been a productive researcher over his 24-year academic career, with over 360 peer-reviewed manuscripts. He has a Scopus H index of 45, an NIH ICite RCR index is 1.52, and weighted RCR of 490. He serves presently as the Director of Clinical Research Facilitation at Duke Orthopaedics, and assists “clinically-based” faculty in achieving scholarship goals. He has mentored countless PhD, ScD, Fellows, Residents, and other trainees in research. Dr. Cook is an experienced database researcher and analyst, having worked with the Nationwide Inpatient Sample (NIS), the Health and Retirement Survey (HRS), FOTO outcomes repository, the Military Database Repository (MDR), and the Neuropoint Quality Outcomes Datasets (QOD).

Sarah Floyd, PhD

Sarah Floyd, PhD is a health services researcher with research interests surrounding treatment variation and treatment effectiveness in musculoskeletal medicine. Dr. Floyd served as a Junior Service Fellow at the Agency for Healthcare Research and Quality in the summer of 2013 and earned her Ph.D. from the University of Florida in 2016. She served as a postdoctoral fellow and research assistant professor at the University of South Carolina and the Center for Effectiveness Research in Orthopaedics (CERortho) from 2016-2020. She is currently an Assistant Professor in the Department of Public Health Sciences at Clemson University. Her current research is focused on generating personalized comparative effectiveness evidence for clinical decision support during the clinical encounter. Her long-term research goal is to discover ways in which we can deliver the best evidence to physicians and patients to inform treatment decisions and improve clinical practice and patient outcomes. She serves as a PI and co-I on numerous federally funded awards, and enjoys leading research projects within the health system and working collaboratively with clinicians and other researchers.

Steven George, PT, PhD, FAPTA

Steven Z. George PT, PhD, FAPTA completed his physical therapy training at West Virginia University, research training at the University of Pittsburgh, and a postdoctoral fellowship at the University of Florida.  Dr. George’s primary interest is research involving biopsychosocial models for the prevention and treatment of chronic musculoskeletal pain disorders.  Dr. George is an active member of several professional associations and has had his research funded by the National Institutes of Health, Department of Defense, and Patient Centered Outcomes Research Institute.  He was a participant in the 2018 National Academies of Science, Engineering, and Medicine workshop The Role of Nonpharmacological Approaches to Pain Management: Proceedings of a Workshop and has been active in developing clinical practice guidelines with the Orthopaedic Academy of the American Physical Therapy Association and the American Psychological Association.

Dr. George and his collaborators have authored over 330 peer-reviewed publications in leading pain research, physical therapy, medical, orthopaedic, and rehabilitation journals. Dr. George has been recognized with prestigious research awards from the American Pain Society (now defunct), the American Physical Therapy Association, and the International Association for the Study of Pain.  For example, in 2016 he was the 21st John H.P. Maley Lecturer delivering Pain Management: Roadmap for Revolution and in 2022 he was recognized with the Marian Williams Research Award In 2020, Duke University School of Medicine recognized Dr. George as the Laszlo Ormandy Distinguished Professor in Orthopaedic Surgery for extraordinary scholarship in advancing science and improving human health related to my work in acute and chronic musculoskeletal pain.

Thomas Noonan, MD

Dr. Noonan is a board-certified orthopedic surgeon specializing in the treatment of injuries and conditions affecting the shoulder, elbow, and knee. His interest in sports led him to orthopedics and sports medicine. Today, his expertise is focused on athletes who use their arms for throwing – baseball players as an example – and injuries to the shoulder, elbow, and knee. Dr. Noonan’s patients include professional athletes, middle-aged weekend warriors, and even older non-athletes.

Stephen Pill, MD, MSPT

Stephan Pill, MD, MSPT is an Associate Professor of Orthopaedic Surgery at University of South Carolina School of Medicine-Greenville School of Medicine and serves as the Associate Fellowship Director of the Sports Medicine and Shoulder Reconstruction Fellowship at the Steadman Hawkins Clinic of the Carolinas (Prisma Health, Greenville, South Carolina). He has enjoyed the collaboration with ATI physical therapy under the research expertise and guidance of Drs. Thigpen and Shanley. Dr. Pill is active with clinical research with medical students, residents, fellows, and colleagues. He has 13 years of experience as a busy orthopaedic provider and dedicates time to balance research and education along with his clinical interests. He has published more than 50 peer-reviewed papers and authored textbook and book chapters. He has presented at many regional and national meetings, served as principal investigator on numerous projects, and has been awarded research grants. He works within the Hawkins Foundation research team along with Dr. Kissenberth to guide outcomes related research within a robust orthopaedic clinic.