Pediatric Concussion Biomechanics: What We Need To Know
Concussions are diagnosed based on symptoms, and most assessments are influenced by the patients’ awareness of or willingness to report their symptoms, which undermines our ability to identify biomechanical thresholds associated with concussion using instrumented volunteers. In addition, the biomechanical environment, occasionally captured by sensors in helmets, patches and mouthguards often report limited information about the rotational movements of the head associated with concussion. Animal models can provide a controlled laboratory setting to investigate the relationships between the risk of concussion and the rapid head rotation magnitude and direction, as well has the contributions of age, sex, and previous concussions in the biomechanical thresholds for concussion. Most animal models for traumatic brain injury typically exhibit loss of consciousness, axonal damage, and hemorrhage, often with focal contusions. These animal models are representative of moderate to severe traumatic brain injuries (TBIs), but few mimic the more subtle cognitive and neurofunctional alterations without pathology found in concussion. Thus, animal model-derived biomechanical thresholds are typically for more severe brain injuries than concussion. Regardless, animal models insight into how head impacts and sudden head movements produce brain deformations and how brain deformations result in a spectrum of brain injuries, from mild to severe TBI. Emerging research in objective, involuntary neurofunctional metrics and biomarkers can bridge the gap between human and animal research, and provide important insight into the biomechanics of concussion, to provide a rational foundation for injury prevention and treatment.