Mild head injuries are common occurrences in the United States. 2. If not properly understood and managed, mild head injuries can be unnecessarily costly in terms of lost work days, financial expenditures, and human suffering. 3. If properly understood and treated, most victims of mild head injuries can return to productive lifestyles. 4. Factors that place persons at high risk for more severe symptoms and/or more lengthy recovery periods are easy to conceptualize.