The word concussion, stemming from the Latin word concussion, means to shake violently and has been defined in numerous ways by various academies and subcommittees. A subcommittee of the American Academy of Neurology defined concussion as a trauma-induced alteration in mental status that may or may not involve loss of consciousness. A more inclusive definition made by an international multidisciplinary conference states that a concussion is a brain injury consisting of a complex pathophysiological process affecting the brain, induced by traumatic biomechanical forces. When defining concussion, it is important to keep the following common features in mind:

• It is usually caused by a direct blow to the head, face, neck, or body.
• It typically causes a rapid onset of short-lived neurological symptoms that subside spontaneously.
• It may result ...