Mobility problems are pervasive in older adults. Mobility limitations affect personal independence, need for human help, and quality of life. Limited mobility predicts future health, function, and survival. Like other geriatric syndromes, mobility disorders are caused by diseases and impairments across many organ systems, so evaluation and management require multiple perspectives and disciplines. Health-care providers should be able to assess and treat mobility problems. They should be able to measure and interpret clinical indicators of mobility such as gait speed, the short physical performance battery, and the performance-oriented mobility assessment. They should know the physiological and biomechanical mechanisms underlying normal and abnormal mobility, the differential diagnosis of the causes of mobility disorders, and the approaches to management of mobility problems.
Mobility is the ability to move one's own body through space. Mobility requires force production and feedback control systems to navigate the mass of the body through a three-dimensional environment. Walking is the fundamental mobility task for human life. Mobility also includes a wide range of other important activities that require moving one's body, from turning over in bed to climbing stairs. Mobility tasks have an inherent hierarchical order based on the biomechanical and physiological demands made on the body. This orderedness is apparent in the developmental tasks of infancy and childhood, when mobility independence is first achieved. The simplest and first mobility task is turning over in bed, followed by sitting upright, transfers from lying to sitting and from sitting to standing, locomotion with an increased base of support (like crawling or using a walker), to independent two legged walking, then more challenging tasks like ascending and descending stairs, running, climbing ladders, and sports.
Mobility disability is best defined within a conceptual framework such as that of disablement (Table 115-1). Disability is caused by pathologic processes that lead to organ system impairments and functional limitations. Disability causes handicap by limiting life roles such as work or caregiving. Disability in mobility occurs at the level of the whole person and is manifested by the inability to carry out normal mobility activities like bathing or shopping. Mobility disability is caused by functional limitations in walking, transferring, or climbing stairs, which are, in turn, caused by problems with strength, endurance, coordination, balance, and range of motion. These functional limitations can be caused by numerous pathological processes. Disablement can be modified by psychological, social, and environmental factors. Mobility disability can precipitate a cycle of negative consequences because it often leads to decreased activity, which in turn worsens functional limitations and causes organ system deconditioning, including muscle weakness, loss of joint range of motion, and poor cardiovascular endurance.
Table 115-1 Mobility Disability and the Disablement Process |Favorite Table|Download (.pdf)
Table 115-1 Mobility Disability and the Disablement Process
COMPONENT OF THE DISABLEMENT PROCESS
EXAMPLES RELATED TO MOBILITY DISABILITY
Cardiopulmonary, neurological, and musculoskeletal conditions