Gait disorders in adults and the elderly

Abstract

SummaryHuman gait depends on a complex interplay of major parts of the nervous, musculoskeletal and cardiorespiratory systems. The individual gait pattern is influenced by age, personality, mood and sociocultural factors. The preferred walking speed in older adults is a sensitive marker of general health and survival. Safe walking requires intact cognition and executive control. Gait disorders lead to a loss of personal freedom, falls and injuries and result in a marked reduction in the quality of life. Acute onset of a gait disorder may indicate a cerebrovascular or other acute lesion in the nervous system but also systemic diseases or adverse effects of medication, in particular polypharmacy including sedatives. The prevalence of gait disorders increases from 10 % in people aged 60–69 years to more than 60 % in community dwelling subjects aged over 80 years. Sensory ataxia due to polyneuropathy, parkinsonism and frontal gait disorders due to subcortical vascular encephalopathy or disorders associated with dementia are among the most common neurological causes. Hip and knee osteoarthritis are common non-neurological causes of gait disorders. With advancing age the proportion of patients with multiple causes or combinations of neurological and non-neurological gait disorders increases. Thorough clinical observation of gait, taking a focused patient history and physical, neurological and orthopedic examinations are basic steps in the categorization of gait disorders and serve as a guide for ancillary investigations and therapeutic interventions. This clinically oriented review provides an overview on the phenotypic spectrum, work-up and treatment of gait disorders.

“Walking” through the sensory, cognitive, and temporal degradations of healthy aging

“…Walking speed declines by 1% per year from a mean of 1.3 m/s in 70 years of age to a mean of 0.95 m/s for those over 80 years old …”

“…In order to walk safely and preserve balance in the event of a slip, the body's center of mass must be kept over its base of support. This depends on intact locomotor function for initiating and sustaining rhythmic gait, balance, postural reflexes, as well as the support of the visual, vestibular, proprioceptive, and musculoskeletal systems . Disruption of normal gait due to aging can lead to trips and falls, and can also be a reliable indicator for assessing: (1) difficulties in dealing with particular environmental conditions (e.g., obstacles) and tasks of higher complexity and/or speed; (2) fatigue and cognitive, attentional, or motor load; (3) sensory or muscular degradation and impaired cognition; and (4) psychological status …”

“…Normal aging is characterized by several changes in the musculoskeletal system. These changes result in gait and balance disorders and have been found to increase from around 10% at the age of 60 to more than 60% in people over the age of 80 . Particularly prominent is the deterioration in motor functioning, which is due to tendon stiffness, inefficient transmission of central motor commands (i.e., increased reaction time and decreased muscle contraction speed), and a reduction in muscle mass and strength (particularly in the lower limbs, i.e., quadriceps and ankle dorsiflexion strength) .…”

“…and ), such as walking speed (obtained by assessing the distance in meters covered per minute); cadence (computed by measuring the number of steps per unit of time, e.g., per minute); step width (i.e., the distance from the midpoint to midpoint of both heels) and length (i.e., the distance from the point of foot contact to the point of contralateral foot contact); swing (i.e., the time period during gait initiation when the one foot is not in contact with the ground) and stance time (i.e., the time period when both feet are on the ground); double support phase (%); stride length (i.e., distance covered during one gait cycle measured in cm); and standard deviation of stride length (i.e., the distance covered during one gait cycle; i.e., in cm) and swing time (i.e., the time period when one foot is not in contact with the ground) . The gait patterns of older adults have been characterized by decreases in gait speed, minimum toe clearance, ground reaction force values, and ankle dorsiflexion, but also by increases in body sway, step width, stride duration, double support duration, minimum foot clearance variability, as well as in stride and step length, which consequently decreases the proportion of time spent in the single‐support swing phase of the gait cycle that normally helps to maintain medio‐lateral stability and improve balance, whereas cadence seems to remain largely unaffected (Table ) . Additionally, gait variability in older adults has been implicated as a predictor of increased risk of falling; yet, from a biomechanical point of view, this variability also reflects the ability to adapt limb movement during the walking act so as to increase stability.…”

Automated leg tracking reveals distinct conserved gait and tremor signatures inDrosophilamodels of Parkinson’s Disease and Spinocerebellar ataxia 3

“…For example, patients with Parkinson's disease (PD) exhibit slowed movements (bradykinesia), rigidity and resting tremor 1 , while patients with cerebellar ataxias like Spinocerebellar ataxia Type 3 (SCA3) exhibit stumbling, jerky, uncoordinated movements, and action tremor [2][3][4][5] . The gait and tremor movements exhibited by patients give clues as to the affected brain regions, and are used to inform diagnosis 6 . Pathological gait and tremor cause difficulty for basic tasks required for daily living; yet, the mechanisms and affected neuronal circuitry are poorly described.…”