First identified in 1984, SIS starts with concussion symptoms following an injury. If the person takes a second hit to the head while the symptoms are still active, effects may include herniation and cerebral swelling. Football players are at risk of SIS, based on data collected and assessed by the North Carolina-based National Center for Catastrophic Sports Injury Research.
The effects of SIS are reported to occur only after a second concussive event which provides an obvious window for treatment. For that reason SIS prevention starts with dealing with the concussion. Contrary to popular belief, a concussion doesn’t necessarily mean losing consciousness. In fact, concussion management guidelines state that most cases happen without “blacking out.”