Concussion, a common result of a blow to the head, has been studied the most of all types of head injury. Various injury mechanisms were proposed by researchers to explain their experimental results. Several injury mechanisms hypothesized for cerebral concussions are: (i) shear strains generated by rotation ; (ii) relative displacement between the brain and the skull producing coup/contrecoup cavitation ; (iii) shear deformation or mass movement in the brainstem principally caused by pressure gradients due to impact loading and translational acceleration [6,7]; and (iv) disturbance of consciousness caused by strains affecting the brain in a centripetal sequence of disruptive effect on function and structure. The effects of this sequence always begin at the surface of the brain in the mild cases and extend inwards to affect the core at the most severe levels of trauma [ 14].
Considerable controversy exists within the biome-chanics community regarding the validity of competing hypotheses because they do not always correlate with clinical and pathologic observations. Although both translational and rotational acceleration can individually cause brain injuries in test animals, the severity of impact needed to produce these injuries is much higher than that experienced by humans involved in vehicular crashes or sports collisions. As a matter of fact, there is rarely an impact that is purely rotational or translational in the real world. Because there is no direct way of verifying these hypotheses on living humans, experiments using laboratory animals and computer models will be needed in order to advance knowledge on head injury mechanisms.
Was this article helpful?
Don’t Read this Report. Unless you want to miss out on the most exciting information about Sculpted Muscles in a Decade. Do you long for a better physique with more shapely and defined muscles? If so, you’re not alone! The problem is that while many people would love to have better defined muscles they’re not sure how to go about achieving them.