ABSTRACT
The scientific literature on injury to the brain or spinal cord is enormous, and grows annually. Yet the results are mostly clinical in nature, and often refer to unrepresentative groups of patients selected for study because of special medical conditions. The few epidemiological reports are problematic as well because of methodologic problems and inconsistencies that hinder the comparison of results. Most investigations concerning “head injury” are really about brain injury. In some reports, however, it is unclear whether the authors intended to study brain injury or head injury. Determining brain injury severity has been a long-standing problem. For decades, various systems were employed, and most were nonreproducible because of their subjective nature. Duration of unconsciousness was one of the most consistently used criteria to judge severity, because it was positively correlated with diffuse brain damage. A spinal cord injury that results in loss of motor or sensory function is one of the most catastrophic medical conditions recognized.
