ABSTRACT

Problems with mobility in older adults are common. In the United States, among persons 65 years and older, approximately 19% receive help with walking, 10% have difficulty with bathing, and 8% receive help with bed or chair transfers (1). The rate at which these problems occur increases progressively after age 65 years and climbs sharply after age 80 years, so that, for example, more than 34% of non-institutionalized persons who are 85 years or older have mobility problems (see also Chapters 1 and 8). In this chapter, we shall first focus on how advancing age alters biomechanical capacities relevant to gait-related activities. Then we will review the biomechanics of gait as they apply to older adults, some of the reasons why falls occur during gait, and finally, when a fall occurs, the biomechanical factors that determine whether an injury will result from the fall.