In the January 2011 issue of Exercise and Sport Sciences Reviews, the authors combine their recent studies investigating the biomechanical relationships of concussion with various factors such as playing position, types of play, con-cussive versus subconcussive impacts, location of impacts, and clinical measures of concussion. Through real-time data collection, the authors sought to determine whether an injury threshold for concussion does indeed exist. A discussion of direct and indirect forces related to concussion, as well as the forces being a combination of linear and rotational in head injuries, is reviewed. Authors question why every direct or indirect impact does not result in an injurious episode. Research shows that even if the head does not move, kinetic energy still can be transferred through the skull, resulting in internal, potentially injurious deformations. Also, cerebrospinal fluid protects the brain within the cranium, so not all forces exceed the threshold required to cause the brain to impact the inside walls of the cranium. Athletes who experience a rotational mechanism are thought to encounter rotation of the cerebrum about the brainstem, producing shearing and tensile strains. These types of impacts are thought to result in more episodes of loss of consciousness than linear forces due to the fact that the upper brainstem and midbrain are responsible for alertness and responsiveness.
展开▼
