**1. Introduction and epidemiology**

Worldwide, the number and proportion of elderly people is constantly increasing. The aging of the baby boomers (people born between 1946 and 1964) and longer life spans (the maximum number of years that a human can live) result in a substantial increase in the number and proportion of older adults (who is age ≥ 65).The elderly population is projected to reach to 83, 7 million in the year of 2050 and, by 2050, it is estimated that older adults will represent 20.9% of the U.S. population [1]. With the surge of the elderly population, there will be an increasing number of geriatric trauma patients admit to the emergency departments. Additionally, the rapid growth of these populations will have many significant impacts on public health and economy.

© 2016 The Author(s). Licensee InTech. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. © 2018 The Author(s). Licensee IntechOpen. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Geriatric trauma patients are less likely to be injured than younger people; however, they are more likely to have fatal outcomes. Death rates for Americans have decreased in the last century. Although there is a dramatic decline in deaths from cardiovascular diseseas, heart diseases remain the leading cause of deaths in the elderly. Also, trauma became the more common cause of death. According to the National Center for Health Statistics 2015 report, unintentional injuries became the seventh common cause of death in the elderly [2].
