Objective: To review the underlying pathophysiologic processes of concussive brain injury and relate these neurometabolic changes to clinical sports-related issues such as injury to the developing brain, overuse injury, and repeated concussion.
Data Sources: Over 100 articles from both basic science and clinical medical literature selected for relevance to concussive brain injury, postinjury pathophysiology, and recovery of function.
Data Synthesis: The primary elements of the pathophysiologic cascade following concussive brain injury include abrupt neuronal depolarization, release of excitatory neurotransmitters, ionic shifts, changes in glucose metabolism, altered cerebral blood flow, and impaired axonal function. These alterations can be correlated with periods of postconcussion vulnerability and with neurobehavioral abnormalities. While the time course of these changes is well understood in experimental animal models, it is only beginning to be characterized following human concussion.
Conclusions/Recommendations: Following concussion, cerebral pathophysiology can be adversely affected for days in animals and weeks in humans. Significant changes in cerebral glucose metabolism can exist even in head-injured patients with normal Glasgow Coma Scores, underscoring the need for in-depth clinical assessment in an effort to uncover neurocognitive correlates of altered cerebral physiology. Improved guidelines for clinical management of concussion may be formulated as the functional significance and duration of these postinjury neurometabolic derangements are better delineated.
|2004||Koh JO, Watkinson EJ, Yoon Y-J. Video analysis of head blows leading to concussion in competition Taekwondo. Brain Inj. December 2004;18(12):1287-1296.|
|2012||Effgen GB, Gill E, Morrison B III. A model of repetitive, mild traumatic brain injury and a novel pharmacological intervention to block repetitive injury synergy. In: Proceedings of the 2012 International IRCOBI Conference on the Biomechanics of Injury. September 12-14, 2012; Dublin, Ireland.455-466.|
|2016||Taylor K, Hoshizaki TB, Hoshizaki TB, Gilchrist MD. Dynamic head response and maximum principal tissue strain for helmeted (American football) and non‐helmeted impacts. In: Proceedings of the 2016 International IRCOBI Conference on the Biomechanics of Injury. September 14-16, 2016; Malaga, Spain.217-227.|
|2017||Koncan DA, Zemek R, Gilchrist MD, Hoshizaki TB. Helmet construction influences brain strain patterns for events causing concussion in youth ice hockey. In: Proceedings of the 2017 International IRCOBI Conference on the Biomechanics of Injury. September 13-15, 2017; Antwerp, Belgium.201-210.|
|2011||Gavett BE, Stern RA, McKee AC. Chronic traumatic encephalopathy: a potential late effect of sport-related concussive and subconcussive head trauma. Clin Sports Med. January 2011;30(1):179-188.|
|2003||Guskiewicz KM, McCrea M, Marshall SW, Cantu RC, Randolph C, Barr W, Onate JA, Kelly JP. Cumulative effects associated with recurrent concussion in collegiate football players: the NCAA concussion study. JAMA. November 19, 2003;290(19):2549-2555.|
|2003||McCrea M, Guskiewicz KM, Marshall SW, Barr W, Randolph C, Cantu RC, Onate JA, Yang J, Kelly JP. Acute effects and recovery time following concussion in collegiate football players: the NCAA concussion study. JAMA. November 19, 2003;290(19):2556-2563.|
|2009||McKee AC, Cantu RC, Nowinski CJ, Hedley-Whyte ET, Gavett BE, Budson AE, Santini VE, Lee H-S, Kubilus CA, Stern RA. Chronic traumatic encephalopathy in athletes: progressive tauopathy after repetitive head injury. J Neuropathol & Exp Neurol. July 2009;68(7):709-735.|
|2002||Collins MW, Lovell MR, Iverson GL, Cantu RC, Maroon JC, Field M. Cumulative effects of concussion in high school athletes. Neurosurgery. November 2002;51(5):1175-1179.|
|2007||Guskiewicz KM, Mihalik JP, Shankar V, Marshall SW, Crowell DH, Oliaro SM, Ciocca MF, Hooker DN. Measurement of head impacts in collegiate football players: relationship between head impact biomechanics and acute clinical outcome after concussion. Neurosurgery. December 2007;61(6):1244-1253.|
|2020||Karton C, Hoshizaki TB, Gilchrist MD. A novel repetitive head impact exposure measurement tool differentiates player position in National Football League. Sci Rep. 2020;10:1200.|
|2016||Antona-Makoshi J. Traumatic Brain Injuries: Animal Experiments and Numerical Simulations to Support the Development of a Brain Injury Criterion [PhD thesis]. Götenburg, Sweden: Chalmers University of Technology; 2016.|
|2016||Schussler E. Assessment, Feedback and Head Accelerations in Youth American Football [PhD thesis]. The Ohio State University; 2016.|
|2016||Virani S. The Effect of Shoulder Pad Design on Head Impact Severity During Shoulder Checks in Ice Hockey [Master's thesis]. Simon Fraser University; Spring, 2016.|
|2014||Rousseau P. Analysis of Concussion Metrics of Real-World Concussive and Non-Injurious Elbow and Shoulder to Head Collisions in Ice Hockey [PhD thesis]. Ottawa, ON: University of Ottawa; 2014.|
|2019||Cournoyer J. Head Impact Severity Associated With Loss of Consciousness and Impact Seizures in Sport-Related Concussions [PhD thesis]. Ottawa, ON: University of Ottawa; 2019.|
|2019||Karton C. Profiling Brain Trauma in Professional American-Style Football and the Implications to Developing Neurological Injury [PhD thesis]. Ottawa, ON: University of Ottawa; 2019.|
|2020||Paiement B. A Comparison of Brain Trauma Profiles Between Elite Men's Rugby Union 15s and Rugby Union 7s Game Play [Master's thesis]. University of Ottawa; 2020.|
|2009||Eucker SA. Effect of Head Rotation Direction on Closed Head Injury in Neonatal Piglets [PhD thesis]. Philadelphia, PA: University of Pennsylvania; 2009.|
|2009||Ibrahim NG. Head Injury Biomechanics in Toddlers: Integrated Clinical, Anthropomorphic Dummy, Animal and Finite Element Model Studies: Implications for Age-Dependence [PhD thesis]. Philadelphia, PA: University of Pennsylvania; 2009.|
|2015||Allison MA. The Performance of Helmet-Based Kinematic Measurement Systems: Importance for Mild Traumatic Brain Injury Prevention [PhD thesis]. Philadelphia, PA: University of Pennsylvania; 2015.|
|2011||Hutchison MG. Concussions in the National Hockey League (NHL): The Video Analysis Project [PhD thesis]. University of Toronto; 2011.|
|2011||Zakaria N. Comparison of Progression of Diffuse Axonal Injury With Histology and Diffusion Tensor Imaging [PhD thesis]. Detroit, MI: Wayne State University; 2011.|
|2020||Harriss A. Cumulative Purposeful Soccer Heading Can Lead to Compensatory Changes in Brain Activity During Combined Moderate Exercise and Cognitive Load in Female Youth Soccer Players [PhD thesis]. University of Western Ontario; 2020.|