Youth Exposure to Repetitive Head Impacts From Tackle Football and Long-term Neurologic Outcomes: A Review of the Literature, Knowledge Gaps and Future Directions, and Societal and Clinical Implications.

Youth participation in contact and collision sports, particularly tackle football, is associated with exposure to repetitive head impacts during a time period when tremendous brain maturation is occurring. Accumulating evidence suggests that exposure to repetitive head impacts from youth tackle football may increase vulnerability to long-term cognitive, neuropsychiatric, and neurologic disturbances. There are limitations to the current literature and conflicting findings exist. Nonetheless, participation in youth football has become a cause of concern to clinicians, scientists, politicians, coaches, parents, and children. The objective of this paper is to review the literature on the long-term cognitive, neuropsychiatric, and neurologic outcomes associated with participation in youth contact and collision sports, with a focus on tackle football. We provide an overview of the empirically derived framework that has served as the foundation for the investigation of youth tackle football and neurologic outcomes. The extant research studies on age of first exposure to tackle football and later-life cognitive and neuropsychiatric functioning, as well as structural brain changes are reviewed. We discuss the limitations of the current evidence, suggest future directions, and conclude with our opinions on societal and clinical implications.